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The data shown below represent the repair cost for a low-impact collision in a simple random sample of mini- and micro-vehicles.

I need help with part "B" Below, please.


The data shown below represent the repair cost for a​ low-impact collision in a simple random sample of​ mini- and​ micro-vehicles. Complete parts​ (a) through​ (d) below.

$ 3148

$ 1002

​$743

​$663

​$773

 

​$1758

​$3345

$ 2044

$ 2608

​$1384

Click here to view the table of critical t-values. LOADING... 

Click here to view page 1 of the standard normal distribution table. LOADING...

Click here to view page 2 of the standard normal distribution table. LOADING...

​(a) Draw a normal probability plot to determine if it is reasonable to conclude the data come from a population that is normally distributed. Choose the correct answer below.

A.


0

2000

4000

-2

-1

0

1

2

Repair Cost ($)

Expected z-score

A normal probability plot has a horizontal axis labeled "Repair Cost (dollars)" from 0 to 4000 in increments of 500 and a vertical axis labeled "Expected z-score" from negative 2 to 2 in increments of 0.5. The graph contains 10 plotted points that follow the general pattern of a line that rises from left to right through (500, negative 1) and (3000, 1), with slight deviation from the line pattern at the tails. The 10 plotted points have coordinates as follows: (650, negative 1.6); (750, negative 1); (750, negative 0.6); (1000, negative 0.4); (1400, negative 0.1); (1750, 0.1); (2050, 0.4); (2600, 0.6); (3150, 1); (3350, 1.6). All coordinates are approximate.

Your answer is correct.B.


0

2000

4000

-2

-1

0

1

2

Repair Cost ($)

Expected z-score

A normal probability plot has a horizontal axis labeled "Repair Cost (dollars)" from 0 to 4000 in increments of 500 and a vertical axis labeled "Expected z-score" from negative 2 to 2 in increments of 0.5. The graph contains 10 plotted points that follow the general pattern of a line that falls from left to right through (500, 1) and (3000, negative 1), with slight deviation from the line pattern at the tails. The 10 plotted points have coordinates as follows: (650, 1.6); (750, 1); (750, 0.6); (1000, 0.4); (1400, 0.1); (1750, negative 0.1); (2050, negative 0.4); (2600, negative 0.6); (3150, negative 1); (3350, negative 1.6). All coordinates are approximate.

C.


0

2000

4000

-4

-2

0

2

4

Repair Cost ($)

Expected z-score

A normal probability plot has a horizontal axis labeled "Repair Cost (dollars)" from 0 to 4000 in increments of 500 and a vertical axis labeled "Expected z-score" from negative 4 to 4 in increments of 1. The graph contains 10 plotted points that follow the general pattern of a line that rises from left to right through (500, negative 2) and (3000, 2), with slight deviation from the line pattern at the tails. The 10 plotted points have coordinates as follows: (650, negative 3.1); (750, negative 2); (750, negative 1.3); (1000, negative 0.8); (1400, negative 0.3); (1750, 0.3); (2050, 0.8); (2600, 1.3); (3150, 2); (3350, 3.1). All coordinates are approximate.

D.


0

2000

4000

-4

-2

0

2

4

Repair Cost ($)

Expected z-score

A normal probability plot has a horizontal axis labeled "Repair Cost (dollars)" from 0 to 4000 in increments of 500 and a vertical axis labeled "Expected z-score" from negative 4 to 4 in increments of 1. The graph contains 10 plotted points that follow the general pattern of a line that falls from left to right through (500, 2) and (3000, negative 2), with slight deviation from the line pattern at the tails. The 10 plotted points have coordinates as follows: (650, 3.1); (750, 2); (750, 1.3); (1000, 0.8); (1400, 0.3); (1750, negative 0.3); (2050, negative 0.8); (2600, negative 1.3); (3150, negative 2); (3350, negative 3.1). All coordinates are approximate.

Is it reasonable to conclude that the data come from a population that is normally​ distributed?

A.

​Yes, because the plotted values are approximately linear.


​(b) Draw a boxplot to check for outliers. Choose the correct answer below.

A.



0

2000

4000







A boxplot has a horizontal axis labeled from 0 to 4000 in increments of 500. The boxplot has the following five-number summary: 650, 750, 1550, 2600, 3350. All values are approximate.

Your answer is correct.

B.



0

2000

4000







A boxplot has a horizontal axis labeled from 0 to 4000 in increments of 500. The boxplot has the following five-number summary: 650, 750, 1950, 3000, 3350. All values are approximate.

C.



0

2000

4000







A boxplot has a horizontal axis labeled from 0 to 4000 in increments of 500. The boxplot has the following five-number summary: 650, 1150, 1950, 3000, 3200. All values are approximate.

D.



0

2000

4000







A boxplot has a horizontal axis labeled from 0 to 4000 in increments of 500. The boxplot has the following five-number summary: 650, 1150, 1550, 3000, 3350. All values are approximate.

Does the boxplot suggest that there are​ outliers?

A.

​Yes, there is at least one point that is outside of the​ 1.5(IQR) boundary.

B.

​No, there are no points that are outside of the​ 1.5(IQR) boundary.

Your answer is correct.

C.

​No, there are no points that are greater than the third quartile or less than the first quartile.

D.

​Yes, there is at least one point that is greater than the third quartile or less than the first quartile.

​(c) Construct and interpret a 95


95​% confidence interval for population mean cost of repair. Select the correct choice and fill in the answer boxes to complete your choice.

​(Round to one decimal place as​ needed.)

A.

The lower bound is ​$

1025.0


1025.0 and the upper bound is ​$

2468.6


2468.6. We are 95


95​% confident that the mean cost of repair is within the confidence interval.

Your answer is not correct.

B.

The lower bound is ​$

nothing


and the upper bound is ​$

nothing


. We are 95


95​% confident that the mean cost of repair is outside of the confidence interval.

​(d) Suppose you obtain a simple random sample of size nequals


=10


10 of a specific type of​ mini-vehicle that was in a​ low-impact collision and determine the cost of repair. Do you think a 95


95​% confidence interval would be wider or​ narrower? Explain.

A.

​Wider, because there is more variability in the data because variability in the repair cost of the car has been added.

B.

​Wider, because taking a second random sample will always lead to a wider confidence interval.

C.

​Narrower, because taking a second random sample will always lead to a narrower confidence interval.

D.

​Narrower, because there is less variability in the data because any variability caused by the different types of vehicles has been removed

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