Judges of a singing competition are voting to select the top two singers for the first and second place in a singing competition with 34 participants. Calculate the number of ways that 34 singers can finish in first, and second places. Fill in the blanks below with the correct numbers. Provide your answer below; FEEDBACK

The answer is (B) Null hypothesis: H0: μ1=μ2

The average tuitions of in-state graduate programs are the same in both school A and school B. Alternative hypothesis: H1: μ1≠μ2 .

The average tuitions of in-state graduate programs are different in both school A and school B.

a) Null hypothesis: The average tuitions of in-state graduate programs are the same in both school A and school B.

Alternative hypothesis: The average tuitions of in-state graduate programs are different in both school A and school B.

b) Null hypothesis: H0: μ1=μ2.

The average tuitions of in-state graduate programs are the same in both school A and school B.)

Alternative hypothesis: H1: μ1≠μ2 .

The average tuitions of in-state graduate programs are different in both school A and school B.

c) You should use a 2-SampTTest as we have two samples with unknown standard deviations.

d) Type I Error: Rejecting the null hypothesis when it is true.

Type II Error: Failing to reject the null hypothesis when it is false.

e) Given information, Sample 1 School

A): Sample size (n1) = 12 Mean (x1)

= $64,000

Standard Deviation (s1) = $8,000

Sample 2 (School B): Sample size (n2) = 16Mean (x2)

= $80,000

Standard Deviation (s2) = $6,000

Level of Significance (α) = 0.10

Calculation of test statistic is shown below:

[tex]t=\frac{(64,000-80,000)-(0)}{\sqrt{\frac{8,000^{2}}{12}+\frac{6,000^{2}}{16}}}= -2.95[/tex]

Degrees of freedom for the test statistic

= (n1-1)+(n2-1) = 11+15

= 26

From the t-tables for a two-tailed test with α= 0.10 and 26 degrees of freedom, we get the value as 1.706.

So, we reject the null hypothesis as the calculated value of t is greater than the tabled value.

Thus, there is sufficient evidence to suggest that the mean tuitions are different for school A and school B.

The difference in average tuition is statistically significant.

Therefore, we accept the alternative hypothesis.

To know more about Null hypothesis, visit:

https://brainly.com/question/30535681

#SPJ11

customers enter Larry's store at a rate of λ per hour, following a Poisson distribution, and the probability of making a sale to any one customer is p, we can calculate the probability of Larry making no sales on any given week and the expectation of sales being made from his store.

To find the probability that Larry makes no sales on any given week, we need to consider the number of customers entering the store during that week. Since customers enter at a rate of λ per hour, the average number of customers in a week can be calculated by multiplying λ by the number of hours in a week. Let's denote this average number as μ. The probability of making no sales to any individual customer is (1-p). As the number of customers follows a Poisson distribution, the probability of making no sales on any given week is given by P(X=0), where X is the number of customers in a week following a Poisson distribution with parameter μ.

The expectation of sales being made from Larry's store can be calculated by multiplying the average number of customers in a week, μ, by the probability of making a sale to any one customer, p. This gives us the expected number of sales made from Larry's store in a week.

In conclusion, to calculate the probability of no sales on any given week, we use the Poisson distribution with the average number of customers, μ. To find the expectation of sales, we multiply the average number of customers, μ, by the probability of making a sale, p. These calculations provide insights into the likelihood of sales in Larry's store and help estimate the expected number of sales in a given week.

learn more about probability here:brainly.com/question/32496411

#SPJ11

The volume of the solid that lies within the sphere x² + y² + z² = 49, above the xy-plane, and below the cone

z = x² y² is 3717π/5 cubic units.

Let us consider the sphere to be S and the cone to be C. As per the given problem statement, we need to find the volume of the solid that lies within the sphere S, above the xy-plane, and below the cone C.

So, the required volume V can be written as: V = [tex]∫∫R (C(x, y) - S(x, y)) dA[/tex]

where C(x, y) and S(x, y) represents the heights of the cone and the sphere from the point (x, y) on the xy-plane, respectively.

R represents the region of the xy-plane projected in the x-y plane. The equation of sphere S is given by x² + y² + z² = 49 ... equation (1)

On comparing this equation with the standard equation of a sphere, we can say that the sphere S has its center at the origin (0, 0, 0) and its radius as 7 units.

Now, let us consider the cone C. Its equation is given as z = x² y² ... equation (2)

On comparing this equation with the standard equation of a cone, we can say that the cone C has its vertex at the origin (0, 0, 0).

Now, we can express z in terms of x and y. From equation (2), we can say that z = f(x, y) = x² y²The volume V can be written as:

V = [tex]∫∫R [f(x, y) - S(x, y)] dA[/tex]

where f(x, y) represents the height of the cone C from the point (x, y) on the xy-plane.

To calculate the integral, we can convert the integral into cylindrical coordinates.

We know that:

V = [tex]∫(θ=0 to 2π) ∫(r=0 to 7) [(r² sin²θ cos²θ) - (49 - r² sin²θ)] r dr dθ[/tex]

After integrating with respect to r and θ, we get:

V = 3717π/5 cubic units

Therefore, the volume of the solid that lies within the sphere x² + y² + z² = 49, above the xy-plane, and below the cone

z = x² y² is 3717π/5 cubic units.

To know more about volume visit:

https://brainly.com/question/28058531

#SPJ11

A function that has a larger maximum include the following: A. Function 1 has a larger maximum.

In order to determine the maximum value of function 1, we would have to take the first derivative with respect to x and then, substitute this x-value into the original function while equating it to zero (0), and then evaluate as follows;

f(x) = −4x² + 6x + 3

f(x) = −8x + 6

0 = −8x + 6

8x = 6

x = 6/8 = 0.75

For the maximum value of function 1, we have:

f(0.75) = −4(0.75)² + 6(0.75) + 3

f(0.75) = 5.25

For the maximum value of function 2, we can logically deduce that it is equal to 3 based on the graph in image attached below.

Read more on maximum and function here: https://brainly.com/question/1800006

#SPJ1

Missing information:

The question is incomplete and the complete question is shown in the attached picture.

The Sturm-Liouville problem y'' + 2y' + y = 0 with boundary conditions y(0) = 0 and y(1) = 0 has eigenfunctions yn = 0 and eigenvalues λn = 0.

The equation is already in self-adjoint form, with the weight function p(x) = 1, and the eigenfunctions are orthogonal with a square norm of 0.

To solve the Sturm-Liouville problem y'' + 2y' + y = 0 with boundary conditions y(0) = 0 and y(1) = 0, we can follow these steps:

a) Find the eigenfunctions and eigenvalues:

Assume the solution has the form y(x) = yn(x), where n is an integer. Substitute this into the differential equation to obtain yn'' + 2yn' + yn = 0. The general solution to this equation is yn(x) = C1e^(-x) + C2xe^(-x), where C1 and C2 are constants. Applying the boundary conditions, we find that C1 = 0 and C2 = 0. Therefore, the eigenfunction is yn(x) = 0 for all n, and the eigenvalue is λn = 0 for all n.

b) Transform the equation to self-adjoint form and find the weight function:

To transform the equation to self-adjoint form, we multiply the equation by a weight function p(x). In this case, p(x) = 1. Multiplying the equation by p(x), we get y'' + 2y' + y = 0. This is already in self-adjoint form, as the coefficients of y'' and y' are equal.

c) Show orthogonality and find the square norm of eigenfunctions:

Since the eigenfunction yn(x) is zero for all n, it is orthogonal to the weight function p(x) = 1. The square norm of the eigenfunction yn(x) is given by ||yn||^2 = ∫[0,1] yn^2(x)p(x)dx = ∫[0,1] 0^2 dx = 0.

In summary, for the given Sturm-Liouville problem, the eigenfunction yn(x) is zero for all n and the eigenvalue is λn = 0 for all n. The equation is already in self-adjoint form, and the weight function is p(x) = 1. The eigenfunctions are orthogonal to the weight function, and their square norm is zero.

To learn more about eigenfunctions click here: brainly.com/question/2289152

#SPJ11

To determine the angle between the force being applied and the wrench, we can use the equation for torque:

Torque = Force * Lever Arm * sin(theta),

where Torque is the magnitude of the torque (9.7 J), Force is the magnitude of the force being applied (45 N), Lever Arm is the length of the wrench (28 cm = 0.28 m), and theta is the angle between the force and the wrench.

Rearranging the equation, we can solve for sin(theta):

sin(theta) = Torque / (Force * Lever Arm).

Substituting the given values into the equation:

sin(theta) = 9.7 J / (45 N * 0.28 m) = 0.0903703704.

To find the angle theta, we can take the inverse sine (arcsin) of sin(theta):

theta = arcsin(0.0903703704) ≈ 5.2 degrees.

Therefore, the angle between the force being applied and the wrench is approximately 5.2 degrees.

Learn more about Torque here -: brainly.com/question/17512177

#SPJ11

(a) If 3^(2k) - 5 is divisible by 4, then 3^(2(k+1)) - 5 is also divisible by 4. By the principle of mathematical induction, we conclude that 3^(2n) - 5 is divisible by 4 for all n ∈ N. (b) If 9^m = 8k + 1, then 9^(m+1) = 8p + 1. By direct proof, we can conclude that 9^n is always one more than a multiple of 8 for all n ∈ N.

In part a, we need to prove by induction that 3^(2n) - 5 is divisible by 4 for all n ∈ N.

To prove this, we will use mathematical induction.

Base Case: For n = 1, we have 3^(2(1)) - 5 = 9 - 5 = 4, which is divisible by 4.

Inductive Step: Assume that 3^(2k) - 5 is divisible by 4 for some arbitrary positive integer k. We need to prove that 3^(2(k+1)) - 5 is also divisible by 4.

Starting with the left-hand side, we have 3^(2(k+1)) - 5 = 3^(2k + 2) - 5 = 9(3^(2k)) - 5 = 9(3^(2k) - 5) + 40.

Since we assumed that 3^(2k) - 5 is divisible by 4, let's say it is equal to 4m for some integer m. Then, we can rewrite the expression as 9(4m) + 40 = 36m + 40.

Now, we need to show that 36m + 40 is divisible by 4. Dividing this expression by 4 gives us 9m + 10. Since 9m is divisible by 4, the remainder is 10.

In part b, we are asked to prove directly that 9^n is one more than a multiple of 8, i.e., 9^n = 8k + 1 for some k ∈ N.

To prove this, we can use a direct proof. Let's consider the base case: for n = 1, we have 9^1 = 9 = 8(1) + 1, which satisfies the given condition.

Now, let's assume that for some arbitrary positive integer m, 9^m = 8k + 1 for some k ∈ N. We need to show that 9^(m+1) = 8p + 1 for some p ∈ N.

Starting with the left-hand side, we have 9^(m+1) = 9^m * 9. By our assumption, we can substitute 9^m with 8k + 1, giving us (8k + 1) * 9 = 72k + 9 = 8(9k + 1) + 1.

Since 9k + 1 is an integer, let's call it p.

Visit here to learn more about integer:

brainly.com/question/929808

#SPJ11

By evaluation,the first limit is equal to 1, and the second limit is equal to 8.

(a) To evaluate the limit lim(z, y) -> (0, 0) of the expression 1² - xy, we substitute x = 0 and y = 0 into the expression:

lim(z, y) -> (0, 0) (1² - xy) = 1² - (0)(0) = 1.

(b) For the limit lim(z, y) -> (0, 0) of the expression 2y + 2³, we substitute y = 0 into the expression:

lim(z, y) -> (0, 0) (2y + 2³) = 2(0) + 2³ = 8.

Therefore, the first limit is equal to 1, and the second limit is equal to 8.

Learn more about limit here:

https://brainly.com/question/12211820

#SPJ11

To determine the distance the spring will be stretched by a specific force, we use Hooke's Law, which states that the force applied is proportional to the displacement of the spring.

(a) To find the work needed to stretch the spring from 38 cm to 42 cm, we can consider the work as the area under the force-displacement curve. Since the force-displacement relationship for a spring is linear, the work is equal to the area of a trapezoid. Using the formula for the area of a trapezoid, we can calculate the work as (base1 + base2) * height / 2. The height is the difference in displacement (42 cm - 38 cm), and the bases are the forces corresponding to the respective displacements. By proportional, we can calculate the force using the given work of 3 J and the displacement change of 14 cm. Then, we calculate the work as (force1 + force2) * (42 cm - 38 cm) / 2.

(b) To determine how far beyond its natural length a force of 45 N will keep the spring stretched, we use Hooke's Law, which states that the force applied to a spring is directly proportional to the displacement of the spring. We can set up the equation 45 N = k * (displacement), where k is the spring constant. Rearranging the equation, we find that the displacement is equal to the force divided by the spring constant. Given that the natural length of the spring is 30 cm, we can subtract this from the displacement to find how far beyond its natural length the spring will be stretched.

Learn more about divided here:

https://brainly.com/question/15381501

#SPJ11

Given, the random variable X is uniformly distributed between 70 and 90. The probability of X having a value between 80 to 95 is [tex]\frac{1}{2}[/tex] or 0.5

The probability density function of a uniformly distributed random variable X is given by:
f(x) = [tex]\frac{1}{(b-a)}[/tex]for a ≤ x ≤ b
where, a and b are the lower and upper bounds of the distribution.
Here, a = 70 and b = 90. Therefore, the probability density function of X is:
f(x) = [tex]\frac{1}{(90-70)}[/tex] = [tex]\frac{1}{20}[/tex] for 70 ≤ x ≤ 90
To find the probability of X having a value between 80 and 95, we need to integrate f(x) from 80 to 90.
The probability of X having a value between 80 to 95 is calculated by integrating the probability density function of X between the limits 80 and 95. The area under the probability density function between these limits gives the probability of X being between 80 and 95. The probability density function of a uniformly distributed random variable X is given by: f(x) = [tex]\frac{1}{(b-a)}[/tex] for a ≤ x ≤ b
where, a and b are the lower and upper bounds of the distribution. Here, a = 70 and b = 90. Therefore, the probability density function of X is:
f(x) = [tex]\frac{1}{(90-70)}[/tex] = [tex]\frac{1}{20}[/tex] for 70 ≤ x ≤ 90
To find the probability of X having a value between 80 and 95, we need to integrate f(x) from 80 to 90.
∫[80, 90] f(x) dx = ∫[80, 90] (1/20) dx
=[tex][\frac{x}{20}]80[/tex] to 90
= [tex]\frac{90}{20}[/tex] - [tex]\frac{80}{20}[/tex]
= [tex]\frac{1}{2}[/tex]

Therefore, the probability of X having a value between 80 to 95 is [tex]\frac{1}{2}[/tex] or 0.5.

Learn more about probability visit:

brainly.com/question/32678715

#SPJ11

The analysis of the statements with regards to the confidence interval, indicates;

1. True; A correct interpretation is "We are 95% confident that the population proportions of Millennials who are fully engaged in the workplace is between 0,07 below and 0.01 above of Gen X'ers who are fully engaged in the workplace".

A confidence interval is a range of values that based on a specified confidence level, is more likely to contain a true value of a population parameter.

The confidence interval for the difference in proportions is the range or values set that is very likely to contain the true or actual difference between two population within a specified confidence level.

The formula for the confidence interval for the difference two population proportion can be presented as follows;

C. I. = (p₁ - p₂) ± z × √(p₁·(1 - p₁)/n₁ +  p₂·(1 - p₂)/n₂)

The specified 95% confidence interval is; C. I. = (-0.07, 0.01)

The interpretation of the above confidence interval is that we are 95% sure that the proportion of Millennials who are fully engaged in the workplace is between -0.07, which is 0.07 less than the population proportion of Gen X'ers who are fulyt engaged and 0.01 above or 0.01 more than the population of Gen X'ers who are fully engaged in the workplace.

1. True;The first statement is therefore true

2. False; More information is required for the second statement, therefore, the second statement is false

3. False; More information is required for the third statement, therefore, the third statement is false

Learn more on confidence interval here: https://brainly.com/question/30536583

#SPJ4

If we assume missing values as zero, the number of participants in each cell would be as follows: Cell A would have 22 participants, cell b would have 49 participants, cell c would have 36 participants and cell d would have 18 participants.

Assuming missing values are zero, we can determine the number of participants in each cell:

Cell a: Control, No Migraine, High Vitamin D - 22 participants

Cell b: Control, No Migraine, Low Vitamin D - 49 participants

Cell c: Control, With Migraine, High Vitamin D - 36 participants

Cell d: Control, With Migraine, Low Vitamin D - 18 participants

These numbers represent the counts of participants based on the given information. In a matched-pair case-control study, participants are paired based on certain characteristics or factors. In this study, the pairs were formed to match individuals with and without migraine headaches within the control group, and their corresponding vitamin D levels were recorded.

The cells indicate the combinations of migraine status and vitamin D levels for the control group. By assuming missing values as zero, we are making the assumption that there are no additional participants in those particular cells.

To learn more about “participants” refer to the https://brainly.com/question/2290843

#SPJ11

We can set up the triple integral as ∫∫∫(z₁ - z₂) rdrdθdz, where z₁ = √(r²) and z₂ = r². The limits of integration would be θ: 0 to π/2, r: 0 to the radius of the region, and z: r² to √(r²). Evaluating this triple integral will give us the volume of the region bounded by the given surfaces in the first octant.

1. In the first octant, the region is confined to positive values of x, y, and z. We can express the given surfaces in cylindrical coordinates, where x = r cos θ, y = r sin θ, and z = z. The equation z = √(x² + y²) represents a cone, and z = x² + y² represents a paraboloid.

2. To set up the triple integral, we need to determine the limits of integration. Since we are working in the first octant, the limits for θ would be from 0 to π/2. For r, we need to find the intersection points between the two surfaces. Equating the expressions for z, we get √(x² + y²) = x² + y². Simplifying this equation yields 0 = x⁴ + 2x²y² + y⁴. This can be factored as (x² + y²)² = 0, which implies x = 0 and y = 0. Therefore, the limits for r would be from 0 to the radius of the region of intersection.

3. Now, we can set up the triple integral as ∫∫∫(z₁ - z₂) rdrdθdz, where z₁ = √(r²) and z₂ = r². The limits of integration would be θ: 0 to π/2, r: 0 to the radius of the region, and z: r² to √(r²). Evaluating this triple integral will give us the volume of the region bounded by the given surfaces in the first octant.

Learn more about triple integral here: brainly.com/question/30404807

#SPJ11

Therefore, the integral ∬, when converted to polar coordinates and evaluated, is equal to 0.

To convert the integral ∬ to polar coordinates, we need to express and in terms of and θ, the polar coordinates.

Given = -8 and = √(64 - ²), we can substitute these expressions into the integral and evaluate it.

∬ = ∫∫ θ

Substituting = -8 and = √(64 - ²):

∫∫√(64 - ²) θ = ∫∫√(64 - (-8)²) θ

Simplifying the expression:

∫∫√(64 - 64) θ = ∫∫0 θ

Since the integrand is 0, the integral evaluates to 0.

To know more about integral,

https://brainly.com/question/31412429

#SPJ11

The probability that at least three carpool is about 0.678

Let us suppose that a commuter is selected randomly. The probability that a person carpools is given as:P(Carpooling) = 10% = 0.1There are 20 commuters in the sample, and the likelihood that at least three carpool can be calculated using the binomial probability formula.The probability of obtaining x successes in n trials is given as:P(x) = nCx * p^x * q^(n-x)where, n = 20p = probability of success (carpool) = 0.1q = probability of failure (not carpool) = 1 - p = 1 - 0.1 = 0.9We need to find the likelihood of at least three successes, i.e., P(X ≥ 3).P(X ≥ 3) = P(X = 3) + P(X = 4) + .... + P(X = 20)Using a binomial probability table, we can calculate this probability as follows: P(X ≥ 3) = 0.678Answer in more than 100 words:We are given that 10% of all commuters in a particular region carpool. Let us suppose that a commuter is selected randomly. The probability that a person carpools is given as:P(Carpooling) = 10% = 0.1We are asked to find the probability that at least three people carpool in a sample of 20 commuters. This can be calculated using the binomial probability formula.The probability of obtaining x successes in n trials is given as:P(x) = nCx * p^x * q^(n-x)where, n = 20p = probability of success (carpool) = 0.1q = probability of failure (not carpool) = 1 - p = 1 - 0.1 = 0.9We need to find the likelihood of at least three successes, i.e., P(X ≥ 3).P(X ≥ 3) = P(X = 3) + P(X = 4) + .... + P(X = 20)Using a binomial probability table, we can calculate this probability as follows:P(X ≥ 3) = 0.678

Therefore, the probability that at least three carpool is about 0.678.

To learn more about probability, visit:

brainly.com/question/31828911

#SPJ11

The probability that at least three people carpool is given as follows:

P(X >= 3) = 0.3231 = 32.31%.

The mass probability formula is defined by the equation presented as follows:

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

The parameters, along with their meaning, are presented as follows:

The parameter values for this problem are given as follows:

n = 20, p = 0.1.

Using a binomial distribution calculator, with the above parameters, the probability is given as follows:

P(X >= 3) = 0.3231 = 32.31%.

More can be learned about the binomial distribution at https://brainly.com/question/24756209

#SPJ4

Using Euler's method with a step size of h = 0.2, we can approximate the solution to the initial value problem at the points x = 4.2, 4.4, 4.6, and 4.8. We complete the table using Euler's method to approximate the values of the solution.

To apply Euler's method, we start with an initial condition and use the derivative equation to calculate the next value. Given the step size h = 0.2, we can use the formula:

y_n+1 = y_n + h * f(x_n, y_n)

where y_n is the current value, x_n is the current x-coordinate, and f(x_n, y_n) is the derivative evaluated at the current point.

Using this formula, we can complete the table provided by calculating the values of y at x = 4.2, 4.4, 4.6, and 4.8. The initial value y_0 and x_0 are given in the table. We substitute these values into the Euler's method formula, using the given step size h = 0.2, to approximate the values of the solution at the specified points.

By performing these calculations, we can fill in the table with the approximated values obtained using Euler's method. Each value is rounded to two decimal places as needed.

To learn more about Euler's method click here

brainly.com/question/30459924

#SPJ11

The area bounded by the curves 4x² + 9y² - 16x - 20 = 0 and y² + 2x - 2y - 1 = 0 can be determined by finding the points of intersection between the two curves.

Then integrating the difference between the y-values of the curves over the interval of intersection.

To find the points of intersection, we can solve the system of equations formed by the given curves: 4x² + 9y² - 16x - 20 = 0 and y² + 2x - 2y - 1 = 0. By solving these equations simultaneously, we can obtain the x and y coordinates of the points of intersection.

Once we have the points of intersection, we can integrate the difference between the y-values of the curves over the interval of intersection to find the area bounded by the curves. This involves integrating the upper curve minus the lower curve with respect to y.

The specific integration limits will depend on the points of intersection found in the previous step. By evaluating this integral, we can determine the area bounded by the given curves.

To know more about bounded by curves click here : brainly.com/question/24475796

#SPJ11

a. The 95% confidence interval for u is approximately (181.9, 245.1).

b. The least number of sample repair times to reduce the width of the confidence interval to below 25 hours is equal to at least 39.

For normally distributed random variable,

Standard deviation = 50

let us consider,

CI = Confidence interval

X = Sample mean

Z = Z-score for the desired confidence level 95% confidence level corresponds to a Z-score of 1.96.

σ = Standard deviation

n = Sample size

To find the confidence interval for the mean repair time, use the formula,

CI = X ± Z × (σ / √n)

The sample repair times are,

183, 222, 303, 262, 178, 232, 268, 201, 244, 183, 201, 140

a.  Find a 95% confidence interval for u,

Calculate the sample mean X

X

= (183 + 222 + 303 + 262 + 178 + 232 + 268 + 201 + 244 + 183 + 201 + 140) / 12

≈ 213.5

Calculate the sample standard deviation (s),

s

= √[(∑(xi - X)²) / (n - 1)]

= √[((183 - 213.5)² + (222 - 213.5)² + ... + (140 - 213.5)²) / (12 - 1)]

≈ 55.7

Calculate the confidence interval,

CI

= X ± Z × (σ / √n)

= 213.5 ± 1.96 × (55.7 / √12)

≈ 213.5 ± 1.96 × (55.7 / 3.464)

≈ 213.5 ± 1.96 × 16.1

≈ 213.5 ± 31.6

≈(181.9, 245.1).

b) . Find the least number of repair times needed to be sampled to reduce the width of the confidence interval to below 25 hours,

The width of the confidence interval is ,

Width = 2× Z × (σ / √n)

To reduce the width to below 25 hours, set up the inequality,

25 > 2 × 1.96 × (50 / √n)

Simplifying the inequality,

⇒25 > 1.96 × (50 / √n)

⇒25 > 98 / √n

⇒√n > 98 / 25

⇒n > (98 / 25)²

⇒n > 38.912

Since the sample size must be an integer, the least number of repair times needed to be sampled is 39.

learn more about confidence interval here

brainly.com/question/31377963

#SPJ4

The critical number of the function g(x) = 3√(64 - x^2) is x = 0. To find the critical numbers of a function, we need to identify the values of x where the derivative of the function is either zero or undefined.

In this case, we are given the function g(x) = 3√(64 - x^2) and need to find its critical numbers.

To find the critical numbers of g(x), we first take the derivative of the function. Let's denote the derivative as g'(x). Applying the chain rule, we have g'(x) = (1/2)(3√(64 - x^2))^(-1/2) * (-2x). Simplifying this expression, we get g'(x) = -x/(√(64 - x^2)).

To find the critical numbers, we set the derivative equal to zero and solve for x. In this case, -x/(√(64 - x^2)) = 0. Since the numerator of this expression is zero, we have -x = 0, which implies that x = 0.

Therefore, the critical number of the function g(x) = 3√(64 - x^2) is x = 0.

To learn more about critical numbers, click here:

brainly.com/question/31339061

#SPJ11

The probability that the sample mean IQ is greater than 120 is 0.46017

From the question, we have the following parameters that can be used in our computation:

Mean = 118

SD = 20

For an IQ with a sample mean greater than 120, we have

x = 120

So, the z-score is

z = (120 - 118)/20

Evaluate

z = 0.10

Next, we have

P = p(z > 0.10)

Evaluate using the z-table of probabilities,

So, we have

P = 0.46017

Hence, the probability is 0.46017

Read more about probability at

brainly.com/question/31649379

#SPJ4

Question

In a large population of college-educated adults, the mean IQ is 118 with a standard deviation of 20. Suppose 200 adults from this population are randomly selected for a market research campaign. The probability that the sample mean IQ is greater than 120 is

The probability that the sample mean iq is greater than 120 is

The result of division 2 + 3i by 2i + 1 is 1.5 - i, using rationalizing technique which involves complex-numbers.

To divide 2 + 3i by 2i + 1, we use the rationalizing technique.

Step 1: Multiply the numerator and denominator by 2i - 1.

(2 + 3i) (2i - 1) / (2i + 1)(2i - 1)

Step 2: Solve the numerator.

4i + 6 - 2i^2 - 3i / 5

Step 3: Simplify the equation.

-2 + 7i/5

Thus, we get the answer as

a - bi = -2/5 + (7/5)i.

To divide complex numbers, we can use this formula as well:

(a + bi) / (c + di)

= [(a * c) + (b * d)] / (c^2 + d^2) + [(b * c) - (a * d)] / (c^2 + d^2)i

Let's apply this formula to the given expression:

(2 + 3i) / (2i)

Here, a = 2,

b = 3,

c = 0, and

d = 2.

Plugging these values into the formula, we get:

=[(2 * 0) + (3 * 2)] / (0^2 + 2^2) + [(3 * 0) - (2 * 2)] / (0^2 + 2^2)i

= (6 / 4) + (-4 / 4)i

= 1.5 - i

Therefore, the result of the division 2 + 3i / 2i is 1.5 - i.

To know more about complex numbers, visit:

https://brainly.com/question/20566728

#SPJ11

To solve for `cos 2θ`, you need to use the identity `cos 2θ = cos²θ - sin²θ`

`cos 2θ = -3/5`.

In order to solve for `cos 2θ`, we need to use the identity `cos 2θ = cos²θ - sin²θ`.

We are given the value of sin θ, which is `sin θ = 2/√5`.

We can substitute this value in the identity to get `cos 2θ = cos²θ - (1 - cos²θ)`.

We can further simplify this expression to `cos²θ + cos²θ - 1`.

Rearranging the equation, we can get `cos²θ = (1 + cos 2θ)/2`.

We can substitute the value of `sin θ` again to get `cos²θ = (1 + cos 2θ)/2

= (1 - (2/√5)²)/2

= (1 - 4/5)/2 = 1/5`.

Solving for `cos 2θ`, we get `cos 2θ = 2cos²θ - 1

= 2(1/5) - 1

= -3/5`.

Therefore, `cos 2θ = -3/5`.

To know more about identity visit :

https://brainly.com/question/29149336

#SPJ11

Finally, substitute the values of x, y, and z back into the expressions obtained in Steps 9, 11, and 13 to obtain the solutions for the system.

To solve the given system of equations:

-4x - 6y - 3z = -2

-6x + 4y + 5z = 14

-5x - 4y - 4z = -10

We can use any suitable method, such as substitution or elimination, to find the values of x, y, and z that satisfy all three equations. Here, we'll use the Gaussian elimination method:

Step 1: Multiply the first equation by 6, the second equation by 4, and the third equation by -5 to make the coefficients of y in the first two equations cancel out:

-24x - 36y - 18z = -12

-24x + 16y + 20z = 56

25x + 20y + 20z = 50

Step 2: Add the first and second equations together:

-24x - 36y - 18z + (-24x + 16y + 20z) = -12 + 56

-48x - 20z = 44

Step 3: Add the first and third equations together:

-24x - 36y - 18z + (25x + 20y + 20z) = -12 + 50

x - 16y + 2z = 38

Step 4: Multiply the third equation by 2:

-48x - 20z = 44

2x - 32y + 4z = 76

Step 5: Add the modified third equation to the fourth equation:

-48x - 20z + (2x - 32y + 4z) = 44 + 76

-46x - 28y = 120

Step 6: Multiply the second equation by 23:

-46x - 28y = 120

-138x + 92y + 115z = 322

Step 7: Add the sixth equation to the fifth equation:

-46x - 28y + (-138x + 92y + 115z) = 120 + 322

-184x + 115z = 442

Step 8: Solve the two equations obtained in Step 5 and Step 7 for x and z:

-46x - 28y = 120 (equation from Step 5)

-184x + 115z = 442 (equation from Step 7)

Step 9: Solve the first equation for x:

x = (120 + 28y) / -46

Step 10: Substitute the value of x in terms of y into the second equation:

-184((120 + 28y) / -46) + 115z = 442

Simplifying:

368y - 276z = 884

Step 11: Solve the equation obtained in Step 10 for y:

y = (884 + 276z) / 368

Step 12: Substitute the value of y in terms of z into the first equation (from Step 9) to find x:

x = (120 + 28((884 + 276z) / 368)) / -46

Step 13: Substitute the values of x and y in terms of z into one of the original equations to find z:

-4x - 6y - 3z = -2

Finally, substitute the values of x, y, and z back into the expressions obtained in Steps 9, 11, and 13 to obtain the solutions for the system.

To know more about expressions  visit:

https://brainly.com/question/28170201

#SPJ11

The value of h for which b is in the plane spanned by a₁ and a₂ is h = 1.

To determine if the vector b is in the plane spanned by vectors a₁ and a₂, we need to check if b can be written as a linear combination of a₁ and a₂.

The plane spanned by a₁ and a₂ consists of all vectors of the form c₁a₁ + c₂a₂, where c₁ and c₂ are scalars.

Let's set up the equation:

b = c₁a₁ + c₂a₂

Substituting the given values:

[5] = c₁ × [1] + c₂ × [-5]

[10] [5]

[h] [-20]

[3]

This equation can be written as a system of linear equations:

c₁ - 5c₂ = 5 (equation 1)

5c₁ - 20c₂ = 10 (equation 2)

-c₁ + 3c₂ = h (equation 3)

To solve for h, we need to find the values of c₁ and c₂ that satisfy all three equations.

Let's solve this system of equations:

From equation 1, we can solve c₁ in terms of c₂:

c₁ = 5 + 5c₂

Substitute this value of c₁ into equation 2:

5(5 + 5c₂) - 20c₂ = 10

25 + 25c₂ - 20c₂ = 10

5c₂ = -15

c₂ = -3

Now substitute the value of c₂ back into c₁:

c₁ = 5 + 5(-3)

c₁ = 5 - 15

c₁ = -10

Now, substitute the values of c₁ and c₂ into equation 3:

-(-10) + 3(-3) = h

10 - 9 = h

h = 1

Therefore, the value of h for which b is in the plane spanned by a₁ and a₂ is h = 1.

Learn more about linear combination click;

https://brainly.com/question/25867463

#SPJ4

Let us assume that a is a single-valued branch of log z. So, e^a = z. Then, da/dz = 1/z and dz/dα = e^α.So, apdz = a'd(e^α) = d(a'e^α) - e^adα. And Sa = ∫C a'dz.

Let C be a closed curve starting and ending at z_0. As e^a is analytic, it follows that a' is also analytic, and so, a' has an anti-derivative, F(z) (say).

Let us assume that C be any closed curve inside 2 and not containing any of a_1, a_2,...,a_n. So, by Cauchy's theorem, ∫C f(z)dz = 0. Therefore, it follows that if y is a curve from z_1 to z_n that does not pass through any of a_1, a_2, ..., a_n, then ∫y f(z)dz = ∫y f(z)dz + ∫C f(z)dz - ∫C f(z)dz = ∫y f(z)dz - ∫C f(z)dz, where C is any closed curve inside 2 and not containing any of a_1, a_2, ..., a_n.

Therefore, ∫y f(z)dz = ∫C f(z)dz. But ∫C f(z)dz = 0 (by Cauchy's theorem). Thus, ∫y f(z)dz = 0, where y is the parameterized curve from z_1 to z_n that does not pass through any of a_1, a_2, ..., a_n.

Therefore, the required statement is proved.

To know more about Cauchy's theorem visit :

https://brainly.com/question/31058232

#SPJ11

If we are given, Power, P is 40 W and Weight, W is 90 kg, we can fill the blanks as 40 Watts = 1.8 kgm/min = 9.56 kcal/min.

We know that Power, P = Work/time

Work done, W = force × distance

Time, t = Work / Power

Therefore, W = (P × t)

Substituting the value of time t = 1 min, we get W = (40 × 1) J = 40 J

Now, Work done, W = force × distance

Therefore, force, F = W / distance

Let the distance be d meter

Therefore, F = W / d Let d = 1 meter

Therefore, F = W / d = 40 N

Now, we know that Power, P = force × velocity

We have force, F = 40 N

Given, mass, m = 90 kg

Let acceleration due to gravity, g = 9.8 m/s²

Now, Force, F = mass × acceleration

Force, F = m × g

Substituting the values of force F and mass m, we get40 = 90 × 9.8 × v

Hence, velocity, v = (40 / 90 × 9.8) m/s ≈ 0.045 m/s1. Work done, W = 40 J

Force, F = 40 N

Velocity, v = 0.045 m/s

Distance, d = 1 meter

We know that Power, P = force × velocity

Therefore, P = F × v

Substituting the values of force and velocity, we get P = 40 × 0.045 ≈ 1.8 kgm/min

Now, we know that 1 kJ = 239.006 kcal

Therefore, Work done in kcal, E = (40/1000) × 239.006 ≈ 9.56 kcal/min

Therefore,40 Watts = 1.8 kgm/min = 9.56 kcal/min.

More on Power: https://brainly.com/question/14949574

#SPJ11

In a classroom with 9 students divided into two groups, we can calculate the probabilities related to John and Tom's placement. This includes the probability of John being in Group I, the probability of Tom being in Group I given that John is in Group I, and the probability of John and Tom being in the same group.

(a) The probability of John being in Group I can be calculated by dividing the number of ways John can be in Group I by the total number of possible outcomes: Probability(John in Group I) = Number of ways John in Group I / Total number of outcomes = 4 / 9.

To learn more about probability here : brainly.com/question/23648662

#SPJ11

The position of the particle is s(t) = 10 + 3t² - t³ - 5t⁴/4.

The position of a particle is determined based on its velocity and initial conditions. In each given scenario, we are provided with the velocity function and initial position information. By integrating the velocity function with respect to time and applying the initial position conditions, we can find the position of the particle at different time points.

39. Given v(t) = sin(t) - cos(t) and s(0) = 0, we can integrate v(t) with respect to t to obtain the position function, s(t). The integral of sin(t) is -cos(t), and the integral of -cos(t) is -sin(t). Applying the initial condition s(0) = 0, we find that the position function is s(t) = -cos(t) + sin(t).

40. For v(t) = 1.5√t and s(4) = 10, we integrate v(t) with respect to t. The integral of √t is (2/3)t^(3/2). Applying the initial condition s(4) = 10, we find that the position function is s(t) = (2/3)t^(3/2) + C. We can determine the constant C by substituting t = 4 and s = 10 into the position function.

41. Given a(t) = 10sin(t) + 3cos(t), s(0) = 0, and s(2T) = 12, we integrate a(t) with respect to t to obtain the velocity function, v(t). Integrating a second time gives us the position function, s(t). By applying the initial conditions s(0) = 0 and s(2T) = 12, we can solve for the constants of integration.

42. For a(t) = 10 + 3t - 3t^2, s(0) = 0, and s(2) = 10, we integrate a(t) twice to find the position function, s(t). By applying the initial conditions s(0) = 0 and s(2) = 10, we can determine the constants of integration.

In each case, the position of the particle can be found by integrating the given velocity function with respect to time and applying the given initial conditions.

to learn more about constant click here:

brainly.com/question/29174258

#SPJ11

The given question is option D.

Given that the equation that most likely represents the sketch below is to be determined.

The given sketch is a straight line passing through the origin and having a slope of 4.

Therefore, the equation of the line is of the form y = mx, where

m = 4.

Hence, among the given options, the equation that represents the given sketch is y = 4x.

The given question is option D, that is, y = 4x.

An equation of a line in slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept.

The given sketch is a straight line passing through the origin.

Hence, the y-intercept of the line is zero.

The given line has a slope of 4.

Therefore, the equation of the line is of the form y = 4x + 0,

which can be simplified as y = 4x.

Thus, the equation that represents the given sketch is y = 4x.

Therefore, the equation that most likely represents the sketch below is y = 4x.

Thus, it can be concluded that the option D, that is, y = 4x represents the sketch below.

To know more about slope-intercept visit:

brainly.com/question/19824331

#SPJ11

a. The coefficient of correlation (r squared) is 0.893. This indicates a strong positive correlation between the number of pages and the book's price.

b. The value of r is 0.946. Since the value of r is close to 1, it suggests a strong positive correlation between the number of pages and the price of the book.

c. According to the trendline, a book that is 560 pages should cost approximately $13.63.

d. According to the trendline, a book that costs $9 should have approximately 407 pages.

a. The scatter diagram with a trendline in Excel is created by plotting the data points for the number of pages (x variable) and the price (y variable) and fitting a trendline to the data. The equation of the trendline is obtained by using Excel's trendline feature, which calculates the best-fit line that minimizes the squared differences between the observed data points and the predicted values on the line. The coefficient of correlation (r squared) is a measure of how well the trendline fits the data. In this case, an r-squared value of 0.893 indicates that approximately 89.3% of the variability in the price can be explained by the number of pages.

b. Pearson's Product Moment Correlation Coefficient (r) measures the strength and direction of the linear relationship between two variables. The value of r ranges from -1 to 1, where values close to -1 or 1 indicate a strong linear relationship and values close to 0 indicate a weak or no linear relationship. In this case, a value of 0.946 indicates a strong positive correlation between the number of pages and the price of the book. This means that as the number of pages increases, the price tends to increase as well.

c. To estimate the cost of a book with 560 pages using the trendline equation, we substitute x = 560 into the equation y = 0.015x + 4.955. This gives us y = 0.015(560) + 4.955 = 13.63. Therefore, according to the trendline, a book with 560 pages should cost approximately $13.63.

d. To determine the number of pages for a book that costs $9 using the trendline equation, we rearrange the equation y = 0.015x + 4.955 to solve for x. By substituting y = 9 into the equation and solving for x, we find x = (9 - 4.955) / 0.015 = 407. Therefore, according to the trendline, a book that costs $9 should have approximately 407 pages

To learn more about the coefficient of correlation, click here:

brainly.com/question/29704223

#SPJ11