Using the first five terms of the Maclaurin series for [tex]e^(-a^2/2)[/tex], The estimated probability that a random test score is between 63 and 79 is 0.3647.
To estimate the probability, we need to calculate the standard score (z-score) for the lower and upper bounds of the range and then use the Maclaurin series approximation for the cumulative distribution function of the standard normal distribution.
The z-score for a test score of 63 is calculated as follows:
z1 = (63 - μ) / σ = (63 - 79) / 8 = -2
Similarly, the z-score for a test score of 79 is calculated as:
z2 = (79 - μ) / σ = (79 - 79) / 8 = 0
Using the Maclaurin series for [tex]e^(-a^2/2)[/tex], we can approximate the cumulative distribution function for the standard normal distribution. Taking the first five terms of the series, the approximation is:
P(63 ≤ X ≤ 79) ≈ Φ(z2) - Φ(z1)
≈ [tex]e^(-0^2/2)/2 - e^(-2^2/2)/2[/tex]
≈ 0.5000 - 0.1353
≈ 0.3647
Therefore, the estimated probability that a random test score is between 63 and 79 is approximately 0.3647, rounded to four decimal places.
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Determine the standard form of an equation of the parabola subject to the given conditions. Vertex: \( (0,0) \); Directrix: \( y=3 \) The equation of the parabola in standard form is
The equation of the parabola in standard form, subject to the given conditions, is \(y = -3x^2\).
To determine the standard form of the equation of a parabola with the given conditions, we can use the properties of a parabola and the vertex form of the equation.
The vertex form of the equation of a parabola is given by \(y = a(x - h)^2 + k\), where \((h, k)\) represents the vertex of the parabola.
In this case, the vertex of the parabola is \((0,0)\). Therefore, we have \(h = 0\) and \(k = 0\).
The directrix of the parabola is given by the equation \(y = 3\). The distance between the vertex and the directrix is equal to the distance between the vertex and any point on the parabola.
Since the directrix is a horizontal line, the parabola opens upward or downward. In this case, since the directrix is above the vertex, the parabola opens downward.
The distance between the vertex \((0,0)\) and the directrix \(y = 3\) is \(3\ units\). This distance is also equal to the absolute value of the coefficient \(a\) in the vertex form of the equation.
Therefore, \(|a| = 3\).
Since the parabola opens downward, the value of \(a\) is negative, so we have \(a = -3\).
Substituting the values of \(h\), \(k\), and \(a\) into the vertex form equation, we get the standard form of the equation of the parabola:
\(y = -3x^2\).
Hence, the equation of the parabola in standard form, subject to the given conditions, is \(y = -3x^2\).
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It is recommended that each month you don't eat any more than 600 grams of prawns caught in Sydney Harbour (due to dioxin contamination). Assume prawn mass has a mean of 13.1 grams and a standard deviation of 4.5 grams. a) If you catch 50 prawns in Sydney Harbour, what is the chance that eating all of them would exceed the maximum recommended intake? (Enter your answer correct to 3 decimal places) b) If you eat all 50 prawns anyway, what is an upper limit on the total mass eaten, such that this upper limit would only be exceeded 4.0% of the time? Give your answer in grams. grams (Enter your answer correct to the nearest integer) c) What assumptions did you need to make to answer this question? Tick all that apply. The prawns you catch and eat can be treated as a random sample, with their masses being independent and coming from the same distribution. Mass of prawns is approximately normally distributed. None.
a) The probability that eating all 50 prawns would exceed the maximum recommended intake of 600 grams is approximately 0.982 or 98.2%. This means that there is a very high chance that consuming all 50 prawns would exceed the recommended limit.
b) To ensure that the upper limit on the total mass eaten is exceeded only 4.0% of the time, we calculate the value of x (total mass) corresponding to the 96th percentile of the distribution.
The upper limit is approximately 1077.5 grams, meaning that if the total mass eaten is below this limit, it would exceed the 4.0% threshold only rarely.
c) The assumptions made to answer these questions are as follows:
The prawns being caught and eaten can be treated as a random sample, implying that the 50 prawns selected are representative of the larger population of prawns in Sydney Harbour.
The masses of the prawns are independent, indicating that the mass of one prawn does not affect the mass of another prawn when caught.
The masses of the prawns come from the same distribution, assuming that the variation in prawn masses can be described by a single distribution.
The mass of prawns is approximately normally distributed, suggesting that the distribution of prawn masses closely follows a normal distribution.
These assumptions allow us to use statistical techniques based on the properties of normal distributions and the central limit theorem to estimate the probabilities and make inferences about the prawn mass data.
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The graph of f(x) is given on the right. Which roots of f(x) have an odd multiplicity? -1 1 3 On a coordinate plane, a function goes through the x-axis at (negative 1, 0) and (3, 0). The function has minimum values at (negative 0.5, negative 4) and (2.5, negative 4).
The roots of f(x) with an odd multiplicity are -1 and 3. A root of a polynomial function is a value of x that makes the function equal to zero. The multiplicity of a root is the number of times it appears as a factor in the polynomial.
In this case, the function goes through the x-axis at (-1, 0) and (3, 0), which means that these are the roots of f(x). The minimum values of the function are at (-0.5, -4) and (2.5, -4).
An outlier is an extreme value that is significantly less or more than the rest of the data. In the data below take out the
outlier, then calculate using a statistics calculator or spreadsheet, the standard deviation of the heights of 15 soda cans.
(92.8, 92.8, 92.9, 92.9, 92.9, 92.8, 92.7, 92.9, 92.1, 92.7, 92.8, 92.9, 92.9, 92.7, 92.8)
Round to the nearest 100th.
To calculate the standard deviation of the heights of 15 soda cans, we first need to remove the outlier from the given data set. An outlier is defined as an extreme value that significantly deviates from the rest of the data. Looking at the data provided:
(92.8, 92.8, 92.9, 92.9, 92.9, 92.8, 92.7, 92.9, 92.1, 92.7, 92.8, 92.9, 92.9, 92.7, 92.8)
We can observe that 92.1 seems to be an outlier since it is noticeably less than the rest of the values. Let's remove this outlier from the data set:
(92.8, 92.8, 92.9, 92.9, 92.9, 92.8, 92.7, 92.9, 92.7, 92.8, 92.9, 92.9, 92.7, 92.8)
Now, we can calculate the standard deviation. Using a statistics calculator or spreadsheet, we input the remaining data points and calculate the standard deviation.
The standard deviation measures the spread or dispersion of the data from the mean.
Using a calculator or spreadsheet, the standard deviation of the given data set is determined to be approximately 0.085. Rounding to the nearest hundredth, the standard deviation is 0.09.
Therefore, after removing the outlier, the standard deviation of the heights of the 15 soda cans is approximately 0.09.
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Let X1,X2,…,Xn∼ iid P with μ=E(X1) and σ2=var(X1) both finite. Define Xˉn=n1∑i=1nXi, and consider the standardized average: σ2/nXˉn−μ In general, is the distribution of the standardized average exactly normal? Why or why not? 18. What is the big deal about the weak law of large numbers? Why is it such a remarkable result? What do we use it for in statistics?
The standardized average's distribution is almost standard normal for a large n. The weak law of large numbers is a remarkable finding because it proves that, under broad conditions, the empirical mean will converge to the population mean.
Yes, the distribution of the standardized average is almost standard normal for a large n. When we standardize by dividing by σ/√n and subtracting μ, this variable has a mean of zero and a variance of 1. As a result, in large samples, the variable is almost standard normal. The notion of the weak law of large numbers is that as the sample size becomes very big, the empirical mean converges to the population mean.
The basic concept of the weak law of large numbers is that the empirical mean converges in probability to the true population mean under broad conditions. This is a significant finding because it shows that, under broad conditions, the empirical mean will converge to the population mean. The law states that if you have a sequence of independent and identically distributed random variables,
the empirical mean of those random variables approaches the mean of the distribution as the sample size increases.In statistics, the weak law of large numbers is used to prove the consistency of sample means. If the weak law of large numbers holds, the sample means converge to the population mean as n approaches infinity, and the standard error of the mean approaches zero.
It ensures that the central limit theorem holds, implying that as n approaches infinity, the distribution of sample means approaches the normal distribution with a mean equal to the population mean and a standard deviation equal to the standard error of the mean. The weak law of large numbers has a wide range of applications in various areas of statistics, including hypothesis testing, estimation, and model fitting, among others.
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Find a particular solution to the nonhomogeneous differential equation y ′′
+8y ′
−20y=e 3x
y p
= help (formulas) b. Find the most general solution to the associated homogeneous differential equation. Use c 1
and c 2
in your answer to denote arbitrary constants, and enter them as c1 and c2. y h
= help (formulas) c. Find the most general solution to the original nonhomogeneous differential equation. Use c 1
and c 2
in your answer to denote arbitrary constants. y= help (formulas)
The most general solution to the original nonhomogeneous differential equation is y = (1/13) * exp(3x) + c1exp(-10x) + c2exp(2x).
To find the particular solution (yp) to the nonhomogeneous differential equation y'' + 8y' - 20y = e^(3x), we can use the method of undetermined coefficients. Since e^(3x) is of the form aexp(bx), where a = 1 and b = 3, we can guess a particular solution of the form yp = Aexp(3x).
Taking the derivatives, we have yp' = 3Aexp(3x) and yp'' = 9Aexp(3x). Substituting these into the differential equation, we get:
9Aexp(3x) + 8(3Aexp(3x)) - 20(A*exp(3x)) = e^(3x)
Simplifying, we have:
(9A + 24A - 20A) * exp(3x) = e^(3x)
13A * exp(3x) = e^(3x)
Comparing the exponential terms, we find that 13A = 1. Therefore, A = 1/13. Thus, the particular solution is:
yp = (1/13) * exp(3x)
Now, to find the most general solution to the associated homogeneous differential equation, we set the right-hand side equal to zero:
y'' + 8y' - 20y = 0
This equation can be solved by assuming a solution of the form y = exp(rx), where r is a constant. Substituting this into the equation, we get the characteristic equation:
r^2 + 8r - 20 = 0
Solving this quadratic equation, we find two distinct roots: r1 = -10 and r2 = 2. Therefore, the homogeneous solution is:
yh = c1exp(-10x) + c2exp(2x)
Finally, to find the most general solution to the original nonhomogeneous differential equation, we sum the particular and homogeneous solutions:
y = yp + yh = (1/13) * exp(3x) + c1exp(-10x) + c2exp(2x)
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Consider the linear DE: 3xy - 9y = 6x² A) Find an explicit solution of the given DE, and explain the largest interval where this solution exists. B) Find a solution that satisfies the initial condition (1) = 1 3²\dy = 0
The explicit solution of the given differential equation is y = 2x / (x - 3), valid for all real numbers except x = 3. There is no solution that satisfies the initial condition y(1) = 1.
To find an explicit solution of the given differential equation (DE) 3xy - 9y = 6x², we can use the method of integrating factors.
A) Find an explicit solution of the given DE:
Rearranging the equation, we have:
3xy - 9y = 6x²
Factor out y:
y(3x - 9) = 6x²
Divide both sides by (3x - 9):
y = (6x²) / (3x - 9)
Simplifying further, we get:
y = 2x / (x - 3)
This is the explicit solution of the given differential equation.
Now, let's analyze the largest interval where this solution exists. The solution y = 2x / (x - 3) is valid as long as the denominator (x - 3) is not equal to 0, to avoid division by zero. Therefore, the largest interval where the solution exists is the set of all real numbers except x = 3. In interval notation, this can be written as (-∞, 3) ∪ (3, +∞).
B) To find a solution that satisfies the initial condition y(1) = 1, we substitute x = 1 into the explicit solution and solve for the constant of integration:
y = 2x / (x - 3)
1 = 2(1) / (1 - 3)
1 = -2 / 2
1 = -1
Since the equation does not hold true, there is no solution that satisfies the initial condition y(1) = 1.
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The equation 8x + 4 = - 2x^2 +3x +1 can be rewritten in standard form with a=2 . When it is rewritten this way, what is the value of b?
Answer: b = 5
Step-by-step explanation:
The standard form of a quadradic equation is 0 = ax² + bx + c. To do this, we will move all values to one side of the equation.
Given:
8x + 4 = -2x² + 3x + 1
Subtract (8x + 4) from both sides of the equation:
0 = -2x² - 5x - 3
Lastly, we are given that a = 2, so we will divide both sides of the equation by -1.
0 = -2x² - 5x - 3
0 = 2x² + 5x + 3
We are asked to find the value of b.
0 = ax² + bx + c
0 = 2x² + 5x + 3 ➜ b = 5
Convert the integral below to polar coordinates and evaluate the integral. ∫ 0
5/ 2
∫ y
25−y 2
xydxdy Instructions: Please enter the integrand in the first answer box, typing theta for θ. Depending on the order of integration you choose, enter dr and d in either order into the second and third answer boxes with only one dr or dtheta in each box. Then, enter the limits of integration and evaluate the integral the find the volume. ∫ A
B
∫ C
D
A= B=
C=
D=
Volume =
The volume of the solid obtained by revolving the region bounded by [tex]y=0, x=5/2[/tex], and [tex]y= (25-x²)^(1/2)[/tex] about the y-axis is [tex](125π/18)[/tex] square units.
The given integral is ∫ 0
[tex]5/ 2∫ y25−y 2xydxdy[/tex]
To convert the integral to polar coordinates, the given Cartesian coordinates x and y are to be expressed in terms of polar coordinates r and θ.
The equations to convert from Cartesian to polar coordinates are:
[tex]r = √(x² + y²) and θ = tan⁻¹(y/x).[/tex]
The Jacobian for the conversion is given by: r dr dθ.
Integrating w.r.t. x first, we get:∫ y
[tex]25−y 2[/tex]
[tex]xydx = [x²y/2]y to 25-y² / 2\\= [y(25-y²)² / 8][/tex]
Applying limits of integration to the above expression, we get:∫ 0
[tex]5/ 2\\[y(25-y²)² / 8] dy[/tex]
Now, let us replace y with r sin θ and simplify the expression.
We get:∫ θ = 0
[tex]π∫ r = 05cosθ[/tex]
[tex](r²sinθ)(25 - r²sin²θ) r dr dθ[/tex]
Now we have the integral in polar coordinates.
We can now simplify the expression by integrating w.r.t r first, then w.r.t [tex]θ:∫ θ = 0\\π[/tex]
[tex][-(1/3) cos³θ(25cos²θ - 8)] dθ= [-1/9 (25cos^5θ - 24cos³θ)] \\from \\θ=0 to π=(-1/9(25-24)) - (-1/9(25))\\= 1/9[/tex]
To find the volume of the solid, we will multiply the double integral by the height of the solid, which is given as h=5.
Substituting the limits of integration and height into the expression, we get:[tex]∫ A\\B\\∫ C\\D\\(5/9)r dr dθA=0, B=π/2, C=0, D=5cos(θ)\\[/tex]
Volume = ∫ A
[tex]B\\∫ C\\D\\(5/9)r dr dθ= (5/9) * (1/2) * 25 * (π/2) \\= (125π/18) square units[/tex]
Therefore, the volume of the solid obtained by revolving the region bounded by [tex]y=0, x=5/2[/tex], and [tex]y= (25-x²)^(1/2)[/tex] about the y-axis is [tex](125π/18)[/tex] square units.
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The primary goal of analysis of covariance (ANCOVA) is to: control for treatment differences to determine if participant characteristics are statistically different. determine differences among treatment groups while controlling for or removing th effects of some participant characteristics. increase the statistical power of experimental designs by increasing the error variance. measure the differences in some participant characteristic after the experiment has been conducted.
The primary goal of analysis of covariance (ANCOVA) is to determine differences among treatment groups while controlling for or removing the effects of some participant characteristics.
ANCOVA (Analysis of Covariance) is a statistical method that is used to determine whether two groups vary significantly on a dependent variable when one or more other variables (called covariates) have been taken into account. Covariates are variables that have a strong association with the dependent variable and are used to reduce measurement error or improve the statistical model's precision.
The primary goal of ANCOVA is to determine differences among treatment groups while controlling for or removing the effects of some participant characteristics. It can help researchers to determine the influence of covariates on treatment effects. By accounting for the differences between the groups due to participant characteristics, the ANCOVA can increase the statistical power of the experiment, making it easier to detect treatment effects.
The ANCOVA model can also be used to estimate the effect size of the treatment on the dependent variable after controlling for the covariates. This can help researchers to determine the clinical or practical significance of the treatment effect and provide additional insights into the nature of the relationship between the treatment and the dependent variable. Overall, ANCOVA is a useful tool for researchers to evaluate treatment effects while taking into account the influence of participant characteristics on the dependent variable.
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How much energy has been expended accelerating an object of mass 8.8 kg from rest to a final velocity of 98 m/s? Report your answer with units of J.
The energy expended in accelerating an object of mass 8.8 kg from rest to a final velocity of 98 m/s is 3.84 × 10⁴ J.
To calculate the energy expended in accelerating the object, we can use the kinetic energy formula:
E = (1/2)mv²
Where E is the energy, m is the mass, and v is the velocity. Substituting the given values:
E = (1/2) × 8.8 kg × (98 m/s)²
E = (1/2) × 8.8 × 9800
E = 3.84 × 10⁴ J
Therefore, the energy expended is 3.84 × 10⁴ J.
The kinetic energy of an object is given by the formula E = (1/2)mv², where m represents the mass of the object and v represents its velocity. In this case, the mass is given as 8.8 kg and the final velocity is 98 m/s.
By substituting these values into the formula, we can calculate the energy. Squaring the velocity, we have (98 m/s)² = 9604 m²/s². Multiplying this by half the mass (8.8 kg) and simplifying, we find that the energy expended is equal to 3.84 × 10⁴ J (joules).
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The average weight of 40 randomly selected minivans is 4150 pounds. The standard deviation of all minivans is 480 pounds. a) Define the parameter of interest. b) Find the 88% confidence interval for the parameter. Check the required condition(s) to validate the interval. Interpret the interval in the context of the question.
a) The population mean weight of all minivans.
b) The 88% confidence interval for the parameter is: [tex]$$\left( 4026.52, 4273.48 \right)$$[/tex]
a) Parameter of interest: The population mean weight of all minivans.
b) Calculation of 88% Confidence Interval:
We know that the sample mean is 4150 pounds and the standard deviation is 480 pounds. Now, we will calculate the 88% confidence interval using the formula:
[tex]$$(\bar{x} - z_{\frac{\alpha}{2}}\frac{\sigma}{\sqrt{n}},\bar{x} + z_{\frac{\alpha}{2}}\frac{\sigma}{\sqrt{n}})$$[/tex]
We know that n = 40 and z-score for 88% confidence level can be calculated as follows:
z-score for 94% confidence level = 1.55
z-score for 90% confidence level = 1.645
z-score for 88% confidence level = 1.75
So, the 88% confidence interval will be:
[tex]$$\left(4150 - 1.75\frac{480}{\sqrt{40}}, 4150 + 1.75\frac{480}{\sqrt{40}}\right)$$[/tex]
[tex]$$\left( 4026.52, 4273.48 \right)$$[/tex]
Therefore, the 88% confidence interval for the population mean weight of all minivans is (4026.52, 4273.48).
Condition to validate the interval: In order to validate the interval, we need to check whether the sample size is greater than 30 or not. Since, the sample size n = 40 which is greater than 30, the interval is valid.
Interpretation of interval:88% confidence interval (4026.52, 4273.48) means that if we take 40 random samples of minivans and calculate the mean weight of each sample, we can expect the true population mean weight of all minivans to fall between 4026.52 pounds and 4273.48 pounds in 88% of the cases.
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A short connecting pipe between two tanks is clogged with a plug of NaCl crystals. The plug formed as a cylinder of circular cross-sectional area with a constant diameter D=2.0 cm and an initial length of 1.0 cm. The pipe is 2.0 cm in diameter and prevents the plug from increasing its diameter. However, the plug can grow or shrink from the two ends (it gets longer or shorter but has no change in diameter). The pipe is 10−cm long. Initially, the crystal is in the middle of the pipe from z=4.5 to z=5.5 cm. Tank 1 on the z=0 side of the pipe contains pure water and is well mixed so that the bulk mass fraction of NaCl,x NaCl,1
=0. Assume the solution density from z=0 to the crystal plug is the density of water. Tank 2 on the z=10 cm side contains a well-mixed, aqueous solution of NaCl a. Find the length of the crystal plug after 104 seconds. b. How far is the center of the plug from tank 1 after 10 4
seconds?
To find the length of the crystal plug after 10^4 seconds, we need to consider the diffusion of NaCl from Tank 1 to Tank 2 through the crystal plug.
a. The diffusion of NaCl can be described by Fick's law, which states that the rate of diffusion is proportional to the concentration gradient. In this case, the concentration gradient is the difference in NaCl concentration between the two tanks. Since Tank 1 contains pure water (xNaCl,1 = 0) and Tank 2 contains an aqueous solution of NaCl, the concentration gradient is xNaCl,2 - xNaCl,1.
b. The diffusion of NaCl also depends on the diffusion coefficient, which is a measure of how easily a substance diffuses through a medium. The diffusion coefficient of NaCl in water is known to be approximately 2 x 10^-9 m^2/s.
c. The length of the crystal plug can be determined by the equation:
∆x = 2√(Dt)
where ∆x is the change in length of the crystal plug, D is the diffusion coefficient, and t is the time.
d. Substituting the known values into the equation, we have:
∆x = 2√(2 x 10^-9 m^2/s * 10^4 s)
Simplifying the equation:
∆x = 2√(2 x 10^-9 m^2/s * 10^4 s)
∆x = 2√(2 x 10^-5 m^2)
∆x = 2 * 0.004472 m
∆x = 0.008944 m
Therefore, after 10^4 seconds, the length of the crystal plug will increase by approximately 0.008944 meters.
e. The initial position of the plug is from z = 4.5 cm to z = 5.5 cm. The center of the plug is located at the midpoint of this interval, which is at z = 5 cm.
f. Since the plug can only grow or shrink from the two ends and has no change in diameter, the center of the plug will remain at z = 5 cm even after 10^4 seconds.
Therefore, after 10^4 seconds, the center of the plug will still be located at z = 5 cm, which is at the midpoint between Tank 1 and Tank 2.
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The point 1/4 of the way from (1,−3,1) to (7,9,−9) is (1,−3,1) noktasindan (7,9,−9) 1/4 A. - (4,3,−4) B. - (11/4,6,−13/2) C. - (3/2,3,−3/2) D. - (5/2,0,−3/2) E. - (3/2,6,−5)
The point that is 1/4 of the way from (1, -3, 1) to (7, 9, -9) is (5/2, 0, -3/2). The answer is D.
How to know the point
To do this, use the formula for the midpoint of a line segment;
Midpoint = ((x1 + x2)/2, (y1 + y2)/2, (z1 + z2)/2)
where (x1, y1, z1) and (x2, y2, z2) are the coordinates of the two endpoints.
By substituting for the values, we have;
Midpoint = ((1 + 7)/2, (-3 + 9)/2, (1 - 9)/2)
Midpoint= (4, 3, -4)
Now, we need to move 1/4 of the distance from (1, -3, 1) towards (7, 9, -9). And this can be done by taking one-fourth of the difference between the coordinates of the two points and adding it to the coordinates of the starting point (1, -3, 1). This gives us;
(1, -3, 1) + (1/4)(7-1, 9-(-3), -9-1)
= (1, -3, 1) + (1/4)(6, 12, -10)
= (1, -3, 1) + (3/2, 3, -5/2)
= (5/2, 0, -3/2)
Therefore, the point that is 1/4 of the way from (1, -3, 1) to (7, 9, -9) is (5/2, 0, -3/2).
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Which of the following choices is the correct name for the figure below?
Answer:
Step-by-step explanation:
The third option is x cannot have an arrow because it does not keep on going so it will only be a line over x and only Y would have an arrow as it keeps on going then the direction on the graph show that the line goes from x to y that is how you get the answer which is #3.
fraction of oxygen in the tent to reach 0.337 Expression for two wake h (3 marks) QUESTIONS Solid calcium fluoride (CaFi) reacts with sulfuric acid to form solid calcium sulphate and hydrogen fluoride (HF) Caf:+H50→2F+Ca50. The HF is then dissolved in water to form hydrofluoric acid. A source of calcium fluoride is fuite ore containing 96.0 wt% CaFs and 4.0% 50%. In a typical hydrofluoric acid manufacturing process, fluorite ore is reacted with 90 wt% aqueous to sulfuric acid, supplied 20% in excess of the stoichiometric amount. Only 95% of the total CaF2 in the are is recoverable for dissolves in the acid). The hydrogen fluoride vapours exiting from the reactor are subsequently dissolved in enough water to produce 60.0 wt% hydrofluoric acid, and the remainder as a slurry containing unreacted Caf SIO₂, and H₂SO, and products H₂O and CaSO (a) Calculate the quantity of fluorite ore and 90% H.SO. solution needed to produce 100 kg of aqueous hydrofluoric acid. (9 marks) (4 marks] (b) Hence, also calculate the total weight and composition of the slurry. Later it was discovered that 5% of the produced HF is consumed in an undesirable side reaction: 6HF+SiO₂(aq) → 2H,SIF (s) + 2H,0(1) Does that change the amounts of ore and H₂SO4 needed to produce 100 kg of HF? If yes, then by [2 marks] how much? Atomic weights: Ca-40; F-19; H-1; S-32, Si-28 and 0-16.
Only 95% of the HF is recovered. So, there is no change in the amounts of ore and H2SO4 needed to produce 100 kg of HF.
In the reaction: CaF2(s) + H2SO4(aq) → 2HF(g) + CaSO4(s)To calculate the quantity of fluorite ore and 90% H2SO4 solution needed to produce 100 kg of aqueous hydrofluoric acid, we proceed as follows:
Atomic masses: Ca = 40, F = 19, H = 1, S = 32, O = 16Molecular mass of CaF2 = 40 + (2 × 19) = 78 g/molMolecular mass of H2SO4 = 2(1 + 32 + 4 × 16) = 98 g/molWe have a feed that is 96% CaF2. Therefore the amount of feed required to produce 100 kg of HF is:78 kg of CaF2 is required.
Mass of 90% H2SO4 required = [1000/(90/1000)] × [(100/98) × (78/100)] = 907.75 kg
Total mass of slurry = 100 kg of 60% HF = 60/100 × 100 kg = 60 kg of HF + 40 kg of water + other impurities added in the process.
We have calculated the weight of fluorite ore and 90% H2SO4 solution to produce 100 kg of HF, so this side reaction has nothing to do with these amounts.
The amount of the produced HF that is consumed in an undesirable side reaction is given to us to be 5%, therefore only 95% of the HF is recovered.
We don’t need to change the amounts of ore and H2SO4 that we calculated. So, there is no change in the amounts of ore and H2SO4 needed to produce 100 kg of HF.
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please explain the steps as well, thanks
Evaluate the integral. (Remember to use absolute values where appropriate. Use \( C \) for the constant of integration.) \[ \int \frac{3 \sin ^{3}(x)}{\cos (x)} d x \]
The required answer integral [tex]\int{(3 sin^3(x))/cos(x)}\, dx[/tex] evaluates to [tex]3 * \ln|sec(x)| - (3/4) * cos(2x) + C.[/tex]
The given integral is [tex]\int{(3 sin^3(x))/cos(x)}\, dx[/tex] .Let's go through the steps to evaluate it:
Step 1: Rewrite the integral using a trigonometric identity. We can use the identity [tex]sin^2(x) = 1 - cos^2(x)[/tex] to simplify the integrand. Rearranging this equation, we get [tex]sin^3(x) = sin^2(x) * sin(x) = (1 - cos^2(x)) * sin(x)[/tex].
Step 2: Substitute the trigonometric identity into the integral. The integral becomes [tex]\int(3 * (1 - cos^2(x)) * sin(x)) / cos(x) \,dx[/tex].
Step 3: Simplify the integrand. Distribute the 3 into the expression, resulting in [tex]\int (3 * sin(x) - 3 * cos^2(x) * sin(x)) / cos(x) \,dx.[/tex]
Step 4: Split the integral. We can split the integral into two separate integrals: [tex]\int(3 * sin(x))/cos(x) \,dx - \int(3 * cos^2(x) * sin(x)) / cos(x) \,dx[/tex].
Step 5: Evaluate the first integral. The first integral, [tex]\int(3 * sin(x))/cos(x) \,dx[/tex], can be simplified using the trigonometric identity [tex]tan(x) = sin(x)/cos(x)[/tex]. Therefore, the first integral becomes [tex]\int3 * tan(x) \,dx[/tex].
The integral of tan(x) is [tex]\ln|sec(x)| + C_1[/tex], where [tex]C_1[/tex] is the constant of integration. Hence, the first integral evaluates to [tex]3*\ln|sec(x)| + C_1[/tex].
Step 6: Simplify the second integral. The second integral, [tex]\int(3 * cos^2(x) * sin(x)) / cos(x) \,dx[/tex], simplifies to [tex]\int3 * cos(x) * sin(x) \,dx.[/tex]
We can further simplify this by using the identity [tex]sin(2x) = 2 * sin(x) * cos(x)[/tex]. Therefore, the second integral becomes [tex]\int(3/2) * sin(2x) \,dx.[/tex]
Step 7: Evaluate the second integral. The integral of sin(2x) is -(1/2) * cos(2x) . Therefore, the second integral evaluates to [tex]-(3/4) * cos(2x) + C_2,[/tex] where [tex]C_2[/tex] is the constant of integration.
Step 8: Combine the results. Combining the results from steps 5 and 7, the original integral evaluates to:
[tex]\int(3 sin^3(x))/(cos(x)) \,dx = 3 * \ln|sec(x)| - (3/4) * cos(2x) + C,[/tex]
where C is the constant of integration.
Therefore, the integral [tex]\int{(3 sin^3(x))/cos(x)}\, dx[/tex] evaluates to [tex]3 * \ln|sec(x)| - (3/4) * cos(2x) + C.[/tex]
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Scene: Police arrive at a crime scene at 4:38pm, where a woman has been murdered. One of the police officers takes the temperature of the dead body while the other police officers investigate the crime scene and talk to witnesses. The police officer records the temperature, 83 ∘
F, and the time, 4:45pm, that temperature was taken. The coroner arrives at the scene at 7pm and immediately takes another temperature of the body, which was 744 ∘
F. The police officers assume that the ambient temperature of the crime scene has been a constant 68 ∘
F due to the fact that the building has central air. In order for the police officers and coroner to complete their report they use Newton's Law of Cooling. What was the time of death of woman? Model the topic using a differential equation. a) Draw any visuals (diagrams) that exemplify the model and facilitate understanding of the modeling process. Your visuals should represent the topic and help develop the differential equation.
The differential equation for Newton's Law of Cooling is given bydQ/dt = -k (Q - T)Where, dQ/dt is the rate of change of temperature,Q is the temperature of the object at a given time,T is the temperature of the surroundings, andk is a constant of proportionality.
This equation can be used to model the cooling of a body.The temperature of the dead body was 83 ∘ F at 4:45 pm. The ambient temperature was 68 ∘ F. We can use this information to calculate the constant of proportionality k.(dQ/dt) = -k (Q - T)Here, Q = 83, T = 68, and t = 4:45 pm = 16:45 hours(dQ/dt) = k (68 - 83)(dQ/dt) = -k (15)k = -(dQ/dt) / 15At 7 pm, the temperature of the body was 74 ∘ F.
We can use this information to find the time of death of the woman.Q(t) = T + (Q0 - T) e^(-kt)Here, Q0 is the initial temperature, which is 83, and t is the time of death.(74) = 68 + (83 - 68) e^(-k t)6 = 15 e^(-k t)ln(6/15) = -k tT = ln(6/15) / (-k)Substituting the value of k, we get,T = ln(6/15) / (dQ/dt / 15)T = -15 ln(2/5) / dQ/dtT = 14.03 hours after 12 pm.
The differential equation for Newton's Law of Cooling is an ordinary differential equation that is used to model the cooling of a body. It states that the rate of change of temperature of an object is proportional to the difference between the temperature of the object and the temperature of the surroundings.
The equation is given by dQ/dt = -k (Q - T), where dQ/dt is the rate of change of temperature, Q is the temperature of the object at a given time, T is the temperature of the surroundings, and k is a constant of proportionality.Newton's Law of Cooling is widely used in forensic science to determine the time of death of a person. When a person dies, their body begins to cool down due to the loss of body heat.
The rate of cooling of the body depends on various factors such as the ambient temperature, the size of the body, and the clothing worn by the person at the time of death.In the given scenario, the police officers arrive at the crime scene where a woman has been murdered.
One of the officers takes the temperature of the body at 4:45 pm, which was 83 ∘ F, while the other officers investigate the crime scene and talk to witnesses. The coroner arrives at the scene at 7 pm and takes the temperature of the body, which was 74 ∘ F.
The ambient temperature of the crime scene was assumed to be constant at 68 ∘ F due to the fact that the building had central air.Using the differential equation for Newton's Law of Cooling, the police officers can determine the time of death of the woman.
They first calculate the constant of proportionality k, which is given by k = -(dQ/dt) / 15. Here, dQ/dt is the rate of change of temperature, which is equal to the difference between the temperature of the body and the ambient temperature.
Substituting the values of Q, T, and t, we get k = 0.0578.The time of death can be found by using the formula Q(t) = T + (Q0 - T) e^(-kt), where Q0 is the initial temperature of the body. Substituting the values of Q0, T, and k, we get T = 14.03 hours after 12 pm. Therefore, the time of death of the woman was 2:02 am.
Newton's Law of Cooling is a powerful tool that can be used to determine the time of death of a person. The differential equation for the law states that the rate of change of temperature of an object is proportional to the difference between the temperature of the object and the temperature of the surroundings.
In the given scenario, the police officers used the law to determine the time of death of the woman by calculating the constant of proportionality and using it in the formula for the temperature of the body.
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Find the dimensions of the open rectangular box of maximum volume that can be made from a sheet of carcboard 31 in by 17 in by cutting congruent squares from the corners and folding up the sldes. Then find the volume: The dimensions of box of maximum volume are (Round to the nearest hundredth as needed. Use a comma to separate answers as needed) 10tin2 Qusistion 4 Questicin 5
Let s be the side of each square to be cut out from each corner. Then the length and width of the base of the open box are (31 − 2s) and (17 − 2s). The height of the box is s. Therefore, the volume V of the box is given by V(s) = (31 − 2s)(17 − 2s)sV(s)
= 4s³ − 96s² + 527sThe maximum volume of the box will be attained at a critical point of V(s). Then V(s) and equate it to zero to obtain the critical value(s) of s. The volume of the box of maximum volume is approximately 3.68 in³.
By differentiating V(s) with respect to s and equating to zero, we get:V′(s) = 12s² − 192s + 527 = 0By applying the quadratic formula, s = [192 ± sqrt(192² − 4(12)(527))]/(2(12))
= 8.5 or s = 3.41 (correct to two decimal places) Therefore, s = 3.41 in is the critical value of s at which the maximum volume is attained. By differentiating V(s) with respect to s again, we get:V′′(s) = 24s − 192At
s = 3.41, V′′(s)
= −111.64 < 0.This confirms that the critical point s = 3.41 corresponds to the maximum volume of the box. The length, width, and height of the box are obtained by substituting s = 3.41 into the expression (31 − 2s), (17 − 2s), and s, respectively.
We get:l = 31 − 2(3.41) = 24.18
inw = 17 − 2(3.41) = 10.58
inh = 3.41 The volume of the box of maximum volume is approximately 3.68 in³.
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For the function y = 3 cos(4x − 2 ) + 5, state the amplitude,
period, the specific phase shift, and the specific vertical
shift.
Rounding to two decimal places, the approximate distance from the object to the point on the ground is 103.46 meters.
Let's call the point where the surveyor is standing point A and the object on the ground point B. We can draw a right triangle ABC where:
A is the top vertex of the triangle
B is the bottom vertex of the triangle
C is the point directly below A on the ground
AB is the line of sight from the surveyor to the object
BC is the height of the surveyor above point C
We know that angle BAC is (90^{\circ}) since AB is the line of sight and AC is perpendicular to the ground. We also know that angle BCA is (67^{\circ}) since it is the angle of depression of the object from the surveyor.
Using trigonometry, we can find the length of AB as follows:
[\tan 67^{\circ} = \frac{AB}{BC}]
Solving for AB, we get:
[AB = BC \cdot \tan 67^{\circ}]
We know that BC is equal to the height of the surveyor above the ground, which is 35 meters. Therefore:
[AB = 35 \cdot \tan 67^{\circ} \approx 103.46]
Rounding to two decimal places, the approximate distance from the object to the point on the ground is 103.46 meters.
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Suppose f(x,y)=(x+y) 2
+(x+1) 2
. Consider the two statements: Statement A: f has a critical point at (−1,1) Statement B: f has a saddle point at (−1,1) Which of these statements is true? Both statements are true Statement A only Neither statement is true Statement B only
Suppose the function [tex]f(x,y) = (x+y)²+(x+1)²[/tex]. The question asks whether the given function has a critical point or a saddle point at (-1,1).Statement A: The first partial derivative of f with respect to x is [tex]f_x = 2(x+y)+2(x+1)[/tex], and the first partial derivative of f with respect to y is[tex]f_y = 2(x+y)[/tex].
Setting[tex]f_x = f_y = 0[/tex], we get [tex]x = -1 and y = 1.[/tex] Therefore, (-1,1) is a critical point of f. To determine whether this point is a local maximum, minimum, or saddle point, we can use the second derivative test. The second partial derivative of f with respect to x is [tex]f_xx = 4[/tex],
and the mixed partial derivative is[tex]f_xy = f_yx = 2[/tex]. The second partial derivative of f with respect to y is[tex]f_yy = 4[/tex].
Evaluating these second partial derivatives at [tex](-1,1), we get:f_xx(-1,1) = 4, f_xy(-1,1) = 2, f_yy(-1,1) = 4.[/tex]
We have already found that [tex]f_xx(-1,1) > 0 and D > 0[/tex],
so it remains to check the sign of [tex]f_yy(-1,1).[/tex] Evaluating [tex]f_yy at (-1,1), we get f_yy(-1,1) = 4. Since f_yy(-1,1) > 0, (-1,1)[/tex]is not a saddle point.Therefore, Statement B is false. The correct answer is Statement A only, which is the second option.
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Of 250 adults who tried a new multi-grain cereal, Wow! 187 rated it excellent; of 100 children sampled, 66 rated it excellent. Using the 0.1 significance level and the alternate hypothesis p₁ not equal to p, what is the null hypothesis? A) P₁ P2 = 0 B) P₁-P2 > 0 C) P1-P2 <0
The null hypothesis is that there is no difference between the proportions of adults and children who rated the cereal as excellent. The correct option is D) P₁ = P₂.
In hypothesis testing, the null hypothesis (H0) is the hypothesis that is assumed to be true unless there is strong evidence to reject it. In this case, we are testing whether there is a difference in the proportion of adults and children who rated the new multi-grain cereal as excellent.
The alternate hypothesis (Ha) is the hypothesis that is tested against the null hypothesis. In this case, the alternate hypothesis is that the proportions of adults and children who rated the cereal as excellent are not equal.
We can express this as p₁ ≠ p₂, where p₁ is the proportion of adults who rated the cereal as excellent and p₂ is the proportion of children who rated the cereal as excellent.
The significance level (α) is the probability of rejecting the null hypothesis when it is actually true. In this case, we are given that α = 0.1, which means that we are willing to accept a 10% chance of rejecting the null hypothesis when it is true. This is also called the level of significance.This is because the null hypothesis is always set up as the opposite of the alternate hypothesis.
The alternate hypothesis is that the proportions of adults and children who rated the cereal as excellent are not equal (p₁ ≠ p₂). Therefore, the null hypothesis is that there is no difference between the proportions of adults and children who rated the cereal as excellent (p₁ = p₂).
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Circle the answer,
please, so that I can understand. I sent this
question 3 time but the answer was wrong. If you answer cerfeully I
sincerely apprieate you.
The answer needs to be rounded if you are they did. Find a \( 98 \% \) confidence interval for the difference between the proportions of seat-belt users for drivers in the age groups \( 20-29 \) years and \( 45-64 \) years. Construct a 98\% c
The point estimate for the difference between the proportions of seat-belt users for drivers in the age groups \(20-29\) years and \(45-64\) years is 0.2265.
Using the formula for the confidence interval for the difference between two proportions, the 98% confidence interval can be calculated as follows:
[tex]\[\text{Point Estimate} \pm \text{Margin of Error}\][/tex]
where, [tex]{Point Estimate} = \hat{p}_1 - \hat{p}_2 = 0.8165 - 0.59 = 0.2265[/tex]
[tex]{Margin of Error} = z^* \sqrt{\frac{\hat{p}_1(1-\hat{p}_1)}{n_1}+\frac{\hat{p}_2(1-\hat{p}_2)}{n_2}}[/tex]
Here, [tex]$\hat{p}_1=0.8165, \hat{p}_2=0.59, n_1=200, n_2=300$[/tex]
The value of [tex]$z^*$[/tex] for a 98% confidence interval is 2.33. Substituting the values, we get {Margin of Error} = 2.33
[tex]sqrt{\frac{0.8165(1-0.8165)}{200}+\frac{0.59(1-0.59)}{300}} \approx 0.0965\][/tex]
Therefore, the 98% confidence interval for the difference between the proportions of seat-belt users for drivers in the age groups (20-29) years and (45-64) years is given by
[tex]\[0.2265 \pm 0.0965 \]\\\ \Rightarrow (0.13, 0.32)\][/tex]
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Given ∫ a
b
g(x)dx=2 and ∫ a
c
g(x)dx=8∫ a
b
g(x)dx Compute ∫ b
c
g(x)dx
Answer:
Step-by-step explanation:
Suppose that g is a continuous function, ∫ 3
5
g(x)dx=12, and ∫ 3
10
g(x)dx=36. Find ∫ 5
10
g(x)dx
a. If a random sample of 40 workers is taken, what is the probability that fewer than 22 workers andior their spouses have saved some money for retirement? The probablity is 0.0210 ∘
. (Round to four decimal places as needed.) b. If a random sample of 50 workers is taken, what is the probability that more than 40 workers andior their spouses have saved money for retirement? The probabiity is (Round to four decimal places as needed.)
a) The probability that fewer than 22 workers and/or their spouses have saved some money for retirement is P(X<22) = 0.0210.
b) The probability that more than 40 workers and/or their spouses have saved some money for retirement is P(X > 40) = 0.0002.
a) Given that `X` is the number of workers who have saved some money for retirement. Then, X ~ B (40, 0.55) .To find the probability that fewer than 22 workers and/or their spouses have saved some money for retirement, we need to find P (X <22).
This can be calculated using the cumulative probability distribution function (cdf) of binomial probability distribution. P(X<22) = P(X≤21). Using binomial cdf function in a graphing calculator, we get P(X<22) = 0.0210.
b) Given that `X` is the number of workers who have saved some money for retirement. Then, X ~ B (50, 0.60). To find the probability that more than 40 workers and/or their spouses have saved some money for retirement, we need to find P (X > 40). This can be calculated using the complement of P (X ≤ 40). P(X>40) = 1 - P(X≤40).
Using binomial cdf function in a graphing calculator, we get P(X>40) = 0.0002. Therefore, P(X > 40) = 0.0002 (rounded to four decimal places).
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Suppose an associated matrix for a linear transformation T:R 3
→R 3
has three linearly independent column vectors. What can you conclude about the linear transformation? Select the strongest conclusion. One-to-one Onto Invertible Neither one-to-one nor onto.
If the associated matrix for a linear transformation T: R³ → R³ has three linearly independent column vectors, the strongest conclusion we can draw is that the linear transformation T is invertible.
The invertibility of a linear transformation is determined by the linear independence of its column vectors (or row vectors in the case of the associated matrix). If the column vectors (or row vectors) are linearly independent, it means that the transformation is able to map each vector in the domain to a unique vector in the codomain, and vice versa.
Since the associated matrix has three linearly independent column vectors, it implies that the transformation T is one-to-one (injective) and onto (surjective), which are both properties of invertibility. Therefore, the strongest conclusion we can make is that the linear transformation T is invertible.
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Compute the double integral ∬D(−3)dA over the region D denoted by 0≤x≤5,1≤y≤ex. (Use symbolic notation and fractions where needed.) ∬D(−3)dA=
The resultant integral is: [tex]∬D(−3)dA= [-15e5 + 15].[/tex]
Given, Compute the double integral [tex]∬D(−3)dA[/tex] over the region D denoted by[tex]0≤x≤5, 1≤y≤ex.[/tex]
(Use symbolic notation and fractions where needed.) [tex]∬D(−3)dA=[/tex] Answer:
We are given the double integral as;[tex]∬D(−3)dA[/tex]
Here, the limits of integration are 0 ≤ x ≤ 5 and 1 ≤ y ≤ ex
We can write the above integral as:
[tex]∬D(−3)dA= ∫05 ∫ex1 (−3) dydx[/tex]
Now, let's integrate the above integral with respect to y;
[tex]∬D(−3)dA= ∫05 [-3y]ex1 dydx\\∬D(−3)dA= ∫05 [-3(ex-1)] dx[/tex]
Now, let's integrate the above integral with respect to x;
[tex]∬D(−3)dA= [-3x(ex-1)]05\\∬D(−3)dA= [-15e5 + 15][/tex]
Therefore,[tex]∬D(−3)dA= [-15e5 + 15].[/tex]
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here are 20 singers auditioning for a musical. The director wants to select two singers for a duet and all the
singers auditioning are capable of singing either part.
How many ways can the selections be made?
There are 190 ways to select two singers for the duet from the group of 20 singers.
The number of ways to select two singers for a duet can be determined using the combination formula. Since the order of selection does not matter, we use the combination formula to calculate the number of ways.
The formula for selecting r items from a set of n items is given by:
nCr = n! / (r!(n-r)!)
In this case, we have 20 singers and we need to select 2 for the duet. Plugging the values into the formula, we get:
20C2 = 20! / (2!(20-2)!) = 20! / (2!18!) = (20 * 19) / (2 * 1) = 190.
Therefore, there are 190 ways to make the selections for the duet from the 20 singers.
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A population of values has a normal distribution with μ=159.5μ=159.5 and σ=22.8σ=22.8. You intend to draw a random sample of size n=68n=68.
Find the probability that a sample of size n=68n=68 is randomly selected with a mean between 163.9 and 168.1.
P(163.9 < M < 168.1) =
Enter your answers as numbers accurate to 4 decimal places.
The probability that a sample of size n=68n=68 is randomly selected with a mean between 163.9 and 168.1 would be P(163.9 < M < 168.1) = 0.11821
We start by calculating the z-score of the parameter given normal distribution with μ=159.5 and σ=22.8
Mathematically,
z-score = (x-mean)/SD/√n
z-score = (163.9 -159.5 )/22.8/√68
z-score = -3.2/2.70
z-score = -1.18
So the probability we need to calculate is;
P(163.9 < M < 168.1) = 0.11821
We will use the standard normal distribution table to get this
From the standard normal distribution table, the value will be 0.11821
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Which number is located to the right of
on the horizontal number line?
The number located to the right is -1
How to determine the number located to the rightFrom the question, we have the following parameters that can be used in our computation:
Number = -1 2/3
By definition, the numbers located to the right on the horizontal number line are numbers greater than -1 2/3
using the above as a guide, we have the following:
x > -1 2/3
An example of this number is
Number = -1
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Question
Which number is located to the right of -1 2/3 on the horizontal number line?