Answer:
The sampling method is independent.
Step-by-step explanation:
Samples are said to be dependent when the data chosen in one sample has an effect on the data to be chosen in the other sample, while samples are said to be independent if the data chosen in one sample has no effect on the data to be chosen on the other sample.
Here, the stock analyst wants to know if there is a difference between the mean rate of return from energy stocks and that from financial stocks, so, he randomly selects 13 energy stocks. Since the energy stocks he chose were randomly selected, it means the data he selected from the energy stock will not dictate the type of data to be selected from the financial stock. Thus, the sampling method is said to be independent.
A pair of shoes usually sells for $70. If the shoes are 30% off, and sales tax is 5%, what is the total price of the shoes, including tax?
Answer:
The total price of the shoes including tax is 51.45
Step-by-step explanation:
You could go about this 2 ways.
One way is if the shoes originally cost $70 and they are now 30% off, it basically means that the discounted price of the shoes is 70% of the original cost, which is $49. Then to find the total price including tax, you need to find 105% of 49, because you are adding 5% to the discounted price(100). When you do the math, you should get the answer 51.45.
The other way to do it is by first finding 30% of 70, which is 21, and then subtracting that from the original price(70) to get the discounted price, $49. Then you need to find 5% of 49 and then add that to 49 to find the total cost w/ tax, which is 51.45.
Calculate the length of the apothem of a regular polygon. A
regular hexagon is shown. What is the length of the apothem,
rounded to the nearest inch? Recall that in a regular hexagon,
the length of the radius is equal to the length of each side of the
hexagon
10 in.
a
5 in
9 in
11 in
4 in
Answer:
9 in
Step-by-step explanation:
For an n-sided polygon, the length of the apothem is ...
a = r·cos(180°/n)
We assume your problem statement is saying the radius is 10 inches. For a hexagon, n=6 and we have ...
a = (10 in)cos(30°) ≈ 8.66 in
Rounded to the nearest inch, the apothem is 9 in.
Determine whether the underlined number is a statistic or a parameter. In a study of all 1700 professors at a college, it is found that 35% own a computer Choose the correct statement below. O Parameter because the value is a numerical measurement describing a characteristic of a sample. Statistic because the value is a numerical measurement describing a characteristic of a population. O Statistic because the value is a numerical measurement describing a characteristic of a sample. Use the given minimum and maximum data entries, and the number of classes, to find the class width, the lower class limits, and the upper class limits minimum = 21, maximum = 120, 8 classes (Type a whole number.) Choose the correct lower class limits below .
A. 21, 33, 47, 59, 72, 86, 98, 112
B. 21.34, 47, 60, 73, 86, 99. 112
Answer:
The first option is correct.
Parameter because the value is a numerical measurement describing a characteristic of population.
Class width = 12.375
B. 21.34, 47, 60, 73, 86, 99. 112 is the lower class limit
Step-by-step explanation:
The first option is correct.
Parameter because the value is a numerical measurement describing a characteristic of population.
Parameter is a measure that describes the entire population.
Statistic basically describes a sample of the population.
From the given information , the entire 1700 professors at a college is the population and only 35 % own a television is a characteristic, called parameter, of population.
Another objective we are to find here is:
Use the given minimum and maximum data entries, and the number of classes, to find the class width, .
Class width = Maximum - Minimum /No of classes
Given that :
Maximum = 120
Minimum = 21
number of classes = 8
Then;
Class width = 120 - 21 /8
Class width = 12.375
From the given information :
B. 21.34, 47, 60, 73, 86, 99. 112 is the lower class limit
Which of the following is the solution to 1 x1 +9 $7?
A XS -2
B. All values are solutions
C. 3-2 and 2-16
D. No solution
Answer:
d. no solution
Explanation:
Step 1 - Subtract nine from both sides of the equation
[tex]|x| + 9 \leqslant 7 \\ |x| + 9 - 9 \leqslant 7 - 9 \\ |x| \leqslant - 2[/tex]
Step 2 - Remove the absolute value
[tex] |x| \leqslant - 2 \\ 2 \leqslant x \leqslant - 2 \\ 2 \leqslant - 2[/tex]
Therefore, since positive two is not less than or equal to negative two, there is no solution.
Composition of the function is commuatative
Answer:
The functions g and f are said to commute with each other if g ∘ f = f ∘ g. Commutativity is a special property, attained only by particular functions, and often in special circumstances. For example, |x| + 3 = |x + 3| only when x ≥ 0. ... The composition of one-to-one functions is always one-to-one.
\
Does coordinate s or coordinate t represent a greater number?
Answer:
t
Step-by-step explanation:
both t and s represent x axis value, t is greater as is on the right side from s
Answer: t
Step-by-step explanation: khan academy
what is an example of a literal question
Answer:
an example of a literal question is "what size do you wear", "what time does the show start", "who was the protagonist in your story" etc
Step-by-step explanation:
A can of beans has surface area 320cm squared . Its height is 14 cm. What is the radius of the circular top?
Steps:
All cans take on the shape of a cylinder, unless you have seen interesting shape of cans like a starfish.
The formula for surface area of a cylinder is
SA = 2πr2 + 2πrh
where:
r = radius
h = height
Since we know the surface area and height, we can plug them in. Note that we can factor out the 2π. You will see why we factor out 2π rather than 2πr.
2π(r2 + (20)r) = 396
2π(r2 + 20r) = 396
Divide both sides of the equation by 2π to isolate the r terms.
r2 + 20r = 63.025
Subtract 63.025 on both sides of the equation.
r2 + 20r - 63.025 = 0
Use the quadratic formula to solve for r:
r = (-b ± √(b2 - 4ac)) / 2a
where:
a = 1
b = 20
c = -63.025
Plug in these values into the formula. You should get two solutions because of the plus/minus sign. Accept the positive value of r.
Please mark brainliest
Hope this helps.
The relationship of variance and mean informs researchers about the spread of data. If a researcher calculates the mean abundance per unit area of a species, and then calculates the variance, the relationship between mean and variance will reflect the distribution pattern.
Which distribution pattern pictured below will have variance greater than the mean?
Answer:
The distribution pattern that will have variance greater than mean is one where the population of species is clustered and thus far from the mean abundance of species per unit area.
This distribution pattern can be found, using the POISSON distribution.
Step-by-step explanation:
Variance is a measure of dispersion while Mean is a measure of central tendency.
The mean is the average of all values (in this case, the abundance or concentration of species per unit area). It is the sum total of all values, divided by the number of values there are.
The variance of a given set of data, on the other hand, is a measure of the spread or distance or dispersal of the data from the mean. It measures the spread between each datum/value and the mean value.
The relationship between mean and variance surely reflects the pattern that the distribution will take. The kind of distribution pattern that will have a greater variance than mean is a Poisson distribution. Sample size is usually large here. Since the variance is greater than the mean, the population is a clustered or clumped distribution.
. A certain coin is a circle with diameter 18 mm. What is the exact area of either face of the coin in terms of p?
Answer:
[tex] r =\frac{D}{2}=\frac{18mm}{2}= 9mm[/tex]
The area is given by:
[tex]A= \pi r^2[/tex]
And replacing we got:
[tex] A=\pi (9mm)^2 =81\pi mm^2[/tex]
So then we can conclude that the area of the coin is [tex] 81\pi[/tex] mm^2
Step-by-step explanation:
For this case we know that we have a coin with a diamter of [tex] D =18mm[/tex], and by definition the radius is given by:
[tex] r =\frac{D}{2}=\frac{18mm}{2}= 9mm[/tex]
The area is given by:
[tex]A= \pi r^2[/tex]
And replacing we got:
[tex] A=\pi (9mm)^2 =81\pi mm^2[/tex]
So then we can conclude that the area of the coin is [tex] 81\pi[/tex] mm^2
If the measure of angle 2 is (5 x + 14) degrees and angle 3 is (7 x minus 14) degrees, what is the measure of angle 1 in degrees?
2 lines intersect to form 4 angles. From top left, clockwise, the angles are 1, 2, 3, 4.
88 degrees
89 degrees
90 degrees
91 degrees
Answer:
89 degrees
Step-by-step explanation:
The angle 1 is the same as angle 3.
Angle 2 is the same as angle 4.
The sum of these four angles is 360 degrees.
We have that:
Angle 2 = Angle 4 = 7x - 14
Angle 3 = Angle 1 = 5x + 14
Finding x:
Angle 1 + Angle 2 + Angle 3 + Angle 4 = 360
2*(5x + 14) + 2*(7x - 14) = 360
10x + 28 + 14x - 28 = 360
24x = 360
x = 15
Angle 1:
5x + 14 = 5*15 + 14 = 89 degrees
Answer:
I think it is B
Step-by-step explanation:
We know that if the probability of an event happening is 100%, then the event is a certainty. Can it be concluded that if there is a 50% chance of contracting a communicable disease through contact with an infected person, there would be a 100% chance of contracting the disease if 2 contacts were made with the infected person
Answer:
The correct answer to the following question will be "No". The further explanation is given below.
Step-by-step explanation:
Probability (Keeping the disease out of 1 contact)
= [tex]0.5[/tex]
Probability (not keeping the disease out of 1 contact)
= [tex]1-0.5[/tex]
= [tex]0.5[/tex]
Now,
Probability (not keeping the disease out of 2 contact)
= Keeping the disease out of 1 contact × not keeping the disease out of 1 contact
On putting the estimated values, we get
= [tex]0.5\times 0.5[/tex]
= [tex]0.25[/tex]
So that,
Probability (Keeping the disease out of 2 contact)
= [tex]1-0.25[/tex]
= [tex]0.75 \ i.e., 75 \ percent[/tex]
∴ Not 100%
What is the y coordinate of the point that divides the directed line segment from j to k into a ratio of 2 to 3
Answer:
y = [tex]y_{1}[/tex] + rise * 2/5
Step-by-step explanation:
two lines intersect is more than one point
Answer:
FALSE
Step-by-step explanation:
two lines can be parallel- no intersectstwo lines intersect- one pointAn article reported the following data on oxidation-induction time (min) for various commercial oils:87 105 130 160 180 195 135 145 213 105 145151 152 136 87 99 92 119 129(a) Calculate the sample variance and standard deviation. (Round your answers to three decimal places.)s^2 = ________. min^2s = ________. min(b) If the observations were reexpressed in hours, what would be the resulting values of the sample variance and sample standard deviation? Answer without actually performing the reexpression. (Round your answer to three decimal places.)s^2 =______ hr^2s = ______hr
Answer:
Step-by-step explanation:
Mean = (87 + 105 + 130 + 160 + 180 + 195 + 135 + 145 + 213 + 105 + 145 + 151 152 + 136 + 87 + 99 + 92 + 119 + 129)/19 = 129
Variance = (summation(x - mean)²/n
Standard deviation = √(summation(x - mean)²/n
n = 19
Variance = [(87 - 129)^2 + (105 - 129)^2 + (130 - 129)^2+ (160 - 129)^2 + (180 - 129)^2 + (195 - 129)^2 + (135 - 129)^2 + (145 - 129)^2 + (213 - 129)^2 + (105 - 129)^2 + (145 - 129)^2 + (151 - 129)^2 + (152 - 129)^2 + (136 - 129)^2 + (87 - 129)^2 + (99 - 129)^2 + (92 - 129)^2 + (119 - 129)^2 + (129 - 129)^2]/19 = 23634/19 1243.895 min
Standard deviation = √1243.895 = 35.269 min
60 minutes = 1 hour
Converting the variance to hours,
Each division would have been divided by 60². 60² can be factorized out
Variance = 23634/60² = 6.565 hours
Converting the standard deviation to hours, it becomes
√6.565 = 2.562 hours
what is tan B enter your answer as a simplified fraction in the box
Answer:
7/24
Step-by-step explanation:
Tangent is opposite over adjacent. You know that the opposite leg is 14 but you don't know the adjacent.
To find the unknown leg, use Pythagorean theorem so that 50^2-14^2= leg. The length is 48.
14/48= tan B
7/24= tan B
I need help please help
Answer:
Step-by-step explanation:
Note that 28 + 110 + 42 = 180, and that 28 + 42 + 110 = 180 also.
Since all three angles of one triangle are the same as the corresponding angles of the other triangle, the triangles are similar.
HELP! Let f(x) = x + 1 and g(x)=1/x The graph of (fg)(x) is shown below.
Answer:
Step-by-step explanation:
all numbers except y = 1
because (f*g)(x) = 1+1/x
and 1/x cannot be equal to 0
A supermarket is redesigning it’s checkout lanes. Design A has a sample size of 50, sample mean of 4.1 minutes, and sample standard deviation of 2.2 minutes. Design B has a sample size of 50, sample mean of 3.5 minutes, and sample standard deviation of 1.5 minutes. At the 0.05 level of significance, determine if their is evidence that the checkout times of the two systems differ.
Answer:
The calculated value t = 1.57736 < 1.9845 at 5 % level of significance
Null hypothesis is accepted at 5 % level of significance
There is no significance difference between Design A and Design B
Step-by-step explanation:
Given sample size of design A
n₁ = 50
sample mean of design A x⁻₁ = 4.1 minutes
Sample standard deviation S₁ = 2.2 minutes
Given sample size of design B
n₂ = 50
sample mean of design A x⁻₂ = 3.5 minutes
Sample standard deviation S₂ = 1.5 minutes
Null Hypothesis : H₀ : There is no significance difference between Design A and Design B
Alternative Hypothesis : H₁:There is significance difference between Design A and Design B
Level of significance ∝ = 0.05
Test statistic
[tex]t = \frac{x^{-} _{1}- x^{-} _{2} }{\sqrt{S^{2} (\frac{1}{n_{1} }+\frac{1}{n_{2} }) } }[/tex]
where
[tex]S^{2} = \frac{n_{1} S_{1} ^{2} +n_{2} S^2_{2} }{n_{1} +n_{2} -2}[/tex]
[tex]S^{2} = \frac{50 (2.2)^{2} +50(1.5)^2}{50+50-2}[/tex]
On calculation , we get
S² = 3.6173
Test statistic
[tex]t = \frac{4.1-3.5}{\sqrt{3.617(\frac{1}{50} +\frac{1}{50} }) }[/tex]
On calculation , we get
t = 1.57736
Degrees of freedom
ν = n₁ + n₂ -2 = 50 +50 -2 =98
t₀.₀₂₅ ,₉₈ = 1.9845
The calculated value t = 1.57736 < 1.9845 at 5 % level of significance
null hypothesis is accepted
A physicist examines 25 water samples for nitrate concentration. The mean nitrate concentration for the sample data is 0.165 cc/cubic meter with a standard deviation of 0.0783. Determine the 80% confidence interval for the population mean nitrate concentration. Assume the population is approximately normal. Step 1 of 2 : Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answer:
The 80% confidence interval for the the population mean nitrate concentration is (0.144, 0.186).
Critical value t=1.318
Step-by-step explanation:
We have to calculate a 80% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=0.165.
The sample size is N=25.
When σ is not known, s divided by the square root of N is used as an estimate of σM:
[tex]s_M=\dfrac{s}{\sqrt{N}}=\dfrac{0.078}{\sqrt{25}}=\dfrac{0.078}{5}=0.016[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=25-1=24[/tex]
The t-value for a 80% confidence interval and 24 degrees of freedom is t=1.318.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=1.318 \cdot 0.016=0.021[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 0.165-0.021=0.144\\\\UL=M+t \cdot s_M = 0.165+0.021=0.186[/tex]
The 80% confidence interval for the population mean nitrate concentration is (0.144, 0.186).
Suppose your total taxable income this year is $75,000 you are taxed a rate of 10 percent on the first 25,000 20 percent on the next 25,000 and 30 percent on the final 25,000 what is your total income tax
What is the main issue with plugging values into a function and then graphing it?
Too hard to calculate.
Takes too much time.
Never sure of exact data points.
Does not provide accurate results.
Answer:
B: It takes too much time
Step-by-step explanation:
Once the points have been calculated and then graphed, the solutions to y = 0 can be found. Look for y = 0 and the solutions are -5 and -1. But that takes a lot of time. There must be an easier way, and fortunately, there is.
Do You Understand?
D
4.
1. Essential Question How does an equation
show the relationship between variables and
other quantities in a situation?
Answer:
An equation is basically a way to show a relationship of variables (x,y,a,b, etc) and numbers.
Step-by-step explanation:
Answer:
Shown by explanation.
Step-by-step explanation:
An equation shows a relationship between variables and other factors by defining the variables that are dependent and independent and how these dependent variables are related to the independent variables, this is usually as a result of a prescribed experiment where the relationship of this variables are investigated.
Also remember conditions that favour this experiment must be taken into consideration. And the experiment must always be performed under such conditions.
Kyle is making a frame for a rectangular piece of art. The length of the frame is 3 times the width, as shown below.
TIME REMAINING
54:06
3x
x
If Kyle uses 10 feet of wood to make the frame, what is the length of the frame? Write the answer in decimal form,
0.75
4.60
0.00
Answer:
3.75 feet
Step-by-step explanation:
The length of the frame is 3 times the width.
Let the width be x.
The length will be 3x.
Kyle uses 10 feet of wood to make the frame. This means that the perimeter is 10 feet.
The perimeter of a rectangle is:
P = 2(L + W)
=> 10 = 2(3x + x)
=> 10/2 = 4x
5 = 4x
=> x = 5/4 = 1.25 feet
The width is 1.25 feet. The length is therefore:
1.25 * 3 = 3.75 feet
Which of the following is a radical equation?
X3 - 13
X+ 15 - 13
√x+3-13
x+3 - 13
Answer:
√x+3-13
Step-by-step explanation:
This answer is a radical equation because a square root is used in the equation. This makes the equation radical. The other choices have no square roots so they can't be the answers.
In the transmission of digital information, the probability that a bit has high, moderate, and low distortion is 0.02, 0.07, and 0.91, respectively. Suppose that three bits are transmitted and that the amount of distortion of each bit is assumed to be independent. Let and denote the number of bits with high and moderate distortion out of the three, respectively. Determine the following:
A. fxy(x,y).
B. fx(x).
C. E(X).
D. Are X and Y independent?
Answer:
A. (Table Attached)
B. (See Step 3)
C. 0.06 (See Step 4)
D. NOT independent (See Step 5)
Step-by-step explanation:
STEP 1:Name the probabilities:
p₁ = 0.02, p₂ = 0.07, p₃ = 0.91
q₁ = 1-p₁ = 0.98 , q₂ = 1-p₂ = 0.93 , q₃ = 0.09
Let X and Y be the number of bits with high and moderate distortion out of three.
STEP 2:A.
The function will follow multinomial distribution:
[tex]f_{XY}(x,y) = P(X=x, Y=y) = \frac{3!}{x!y!(3-x-y)!} (p_1^x)(p_2^y)(p_3^{3-x-y})[/tex]
Substitute the values and make a table.
TABLE IN ATTACHMENT
STEP 3:
B.
We calculate marginal distribution by:
[tex]P (X=x)=[/tex] ∑ [tex]P(X=x,Y=y)[/tex]
[tex]fx(x)[/tex] can be found by adding all the probabilities in each row for different value of X
For X=0 , ∑P = 0.94157441
For X=1 , ∑P = 0.057624
For X=2 , ∑P = 0.001176
For X=3 , ∑P =0.000008
STEP 4:C.
The mathematic expectation E is the sum of product of each possibility with its probabiity.
[tex]E(X)=[/tex]∑ [tex]xP(X=x)[/tex]
Find E(X):
[tex]E(X)= (0*0.9415744)+(1*0.057624)+(2*0.001176)+(3*0.000008)[/tex]
[tex]E(X)=0.06[/tex]
STEP 5:
Condition probability states:
[tex]P(A|B)=\frac{P(A,B)}{P(B)}[/tex]
It can also be written as:
[tex]f_{Y|X=1}(y)=\frac{f_{XY}(1,y)}{f_x(1)}[/tex]
Where [tex]f_x(1)\\[/tex] = 0.057624
Calculate the quotient:
[tex]Y|_{x=1}[/tex] = 0 , [tex]f_{Y|_X=1[/tex] = 0.862245
[tex]Y|_{x=1}[/tex] = 1 , [tex]f_{Y|_X=1[/tex] = 0.132653
[tex]Y|_{x=1}[/tex] = 2 , [tex]f_{Y|_X=1[/tex] = 0.000510
[tex]Y|_{x=1}[/tex] = 3 , [tex]f_{Y|_X=1[/tex] = 0
Find the dependency:
[tex]f_{XY}(y)=f_X(x)f_Y(y)[/tex]
We found that
[tex]f_{Y|_X=1[/tex] = 0.862245
Calculate [tex]f_Y(1)[/tex] from summing the column from the table
[tex]f_Y(1)=0.17428341+0.007644+0.000084\\f_Y(1)=0.18201141[/tex]
Which are not equal.
Conclusion:
X and Y are NOT Independent
PEOPLE! THIS IS URGENT! PLEASE HELP ME!!!! If the product 3/2 · 4/3 · 5/4 · 6/5 ·…· a/b =9, what is the sum of a and b?
Answer:
35
Step-by-step explanation:
3/2 · 4/3 · 5/4 · 6/5 ·…· a/b =9
a+b=?
------
all numbers get cancelled apart from the first denominator and the last numerator:
1/2*a= 9
a= 18then
b= a-1= 18-1= 17a+b= 18+17= 35
What’s the correct answer for this?
Answer:
34°
Step-by-step explanation:
According to the theorem, "any two angles in the same segmant are congruent"
<BED = <BCD
So
<BED = 34°
In a game of cards, a bridge is made up of 13 cards from a deck of 52 cards. What
is the probability that a bridge chosen at random contains
6 of one suit, 4 of another, and 3 of another?
Answer:
Probabilty= 4.171. *10^-4
Step-by-step explanation:
bridge is made up of 13 cards
probability that a bridge chosen at random contains
6 of one suit, 4 of another, and 3 of another
Probabilty of 6 = 13C6
Probabilty of 4 = 13C4
Probabilty of 3 = 13C3
Then total= 53C13
Probabilty =( 13C6*13C4*13C3)/53C13
Probabilty=( 1716*715*286)/53C13
Probabilty= 4.171. *10^-4
Classify the triangle by its sides, and then by its angles.
128 degrees
26 degrees
26 degrees
16 cm
16 cm
28 cm
Classified by its sides, the triangle is a(n)
▼
isosceles
scalene
equilateral
triangle.
Classified by its angles, the triangle is a(n)
▼
obtuse
acute
right
triangle.
