Question 1

Use the following 
Select the answer closest to the specified areas for a N(0, 1) density.
-The area to the left of z = -1.52
A) 0.064
B) 0.106
C) 0.936
D) 0.147

Accepted Answer

A

Question 2

Use the following 
Select the answer closest to the specified areas for a N(0, 1) density.
-The area to the right of z = -0.47
A) 0.341
B) 0.77
C) 0.681
D) 0.319

Accepted Answer

C

Question 3

Use the following 
Select the answer closest to the specified areas for a N(0, 1) density.
-The area between z = 0.51 and z = 2.79.
A) 0.695
B) 0.302
C) 0.692
D) 0.997

Accepted Answer

B

Question 4

Use the following 
Select the answer closest to the specified areas for a N(0, 1) density.
-The area outside of the interval z = -2.13 and z = 1.11.
A) 0.133
B) 0.017
C) 0.85
D) 0.15

Accepted Answer

The area outside the interval z = -2.13 and z = 1.11 is the complement of the area within the interval. The area within the interval can be found using the standard normal distribution table, and the complement is approximately 0.15.

Question 5

Use the following
Find the endpoint(s) on a N(0, 1) density with the given property.
-The area to the left of the endpoint is about 0.2.
A) -2.054
B) 0.842
C) -0.842
D) 2.054

Accepted Answer

The area to the left of the endpoint in a standard normal distribution (N(0, 1)) that corresponds to 0.2 is approximately -0.842.

Question 6

Use the following
Find the endpoint(s) on a N(0, 1) density with the given property.
-The area to the right of the endpoint is about 0.45.
A) 0.126
B) 1.695
C) -1.695
D) -0.126

Accepted Answer

The answer of Use the following
Find the endpoint(s) on a...

Question 7

Use the following
Find the endpoint(s) on a N(0, 1) density with the given property.
-The area between $ \pm z $ is about 0.99
A) 2.326
B) 2.225
C) 2.125
D) 2.575

Accepted Answer

The answer of Use the following
Find the endpoint(s) on a...

Question 8

Use the following 
Select the answer closest to the specified areas for a normal density.
-The area to the left of 32 on a N(45, 8) distribution.
A) 0.948
B) 0.052
C) 0.896
D) 0.104

Accepted Answer

The area to the left of 32 on a N(45, 8) distribution is the area under the normal curve to the left of z = (32 - 45) / 8 = -1.625. Using a standard normal table, we find that the area to the left of z = -1.625 is 0.052.

Question 9

Use the following 
Select the answer closest to the specified areas for a normal density.
-The area to the right of 12 on a N(9.4, 1.2) distribution.
A) 0.985
B) 0.97
C) 0.03
D) 0.015

Accepted Answer

To find the area to the right of 12 on a N(9.4, 1.2) distribution, we first calculate the z-score: z = (12 - 9.4) / 1.2 = 2.17. Using a standard normal distribution table or calculator, the area to the right of z = 2.17 is approximately 0.015.

Question 10

Use the following 
Select the answer closest to the specified areas for a normal density.
-The area between 43 and 100 on a N(75, 15) distribution.
A) 0.984
B) 0.952
C) 0.936
D) 0.64

Accepted Answer

The answer of Use the following 
Select the answer closest...

Question 11

Use the following
Find the endpoint(s) on the normal density curve with the given property.
-The area to the left of the endpoint on a N(25, 3) curve is about 0.1.
A) 21.155
B) 28.845
C) 31.978
D) 18.022

Accepted Answer

The z-score corresponding to an area of 0.1 to the left is approximately -1.28. Using the formula for converting a z-score to an x-value in a normal distribution, x = μ + zσ, where μ = 25 and σ = 3, we get x = 25 + (-1.28)(3) = 21.155.

Question 12

Use the following
Find the endpoint(s) on the normal density curve with the given property.
-The area to the right of the endpoint on a N(100, 17) curve is about 0.05.
A) 72.037
B) 100
C) 143.783
D) 127.963

Accepted Answer

The answer of Use the following
Find the endpoint(s) on the...

Question 13

Use the following
Find the endpoint(s) on the normal density curve with the given property.
-The symmetric middle area on a N(66, 6) curve is about 0.9.
A) 54.241 and 77.759
B) 56.131 and 75.869
C) 61.953 and 70.047
D) 59.098 and 72.902

Accepted Answer

The symmetric middle area of 0.9 on a normal distribution curve corresponds to the central 90% of the data. For a N(66, 6) distribution, the endpoints can be found using the z-scores that correspond to the 5th and 95th percentiles, which are approximately -1.645 and 1.645. Calculating these values gives endpoints of approximately 56.131 and 75.869.

Question 14

Use the following
It is generally believed that the heights of adults males in the U.S. are approximately normally distributed with mean 70 inches (5 feet, 10 inches) and standard deviation 3 inches and that the heights of adult females in the U.S. are also approximately normally distributed with mean 64 inches (5 feet, 4 inches) and standard deviation 2.5 inches. A small university is considering custom ordering beds for their dorm rooms. Answer the following questions about the lengths of beds in dorm rooms at this university.
-Draw a sketch of the distribution of men's heights and label at least three points on the horizontal axis.

Accepted Answer