Question 1

For the binomial distribution with the given values for n and p
-n = 12 and p = .5

Accepted Answer

A) Normal approximation is not suitable. 
B) Normal approximation is suitable. 
A) Normal approximation is not suitable. 
B) Normal approximation is suitable.

Question 2

Solve the problem.
-Assume that $\mathrm { z }$ scores are normally distributed with a mean of 0 and a standard deviation of 1 . If $\mathrm { P } ( \mathrm { z } > \mathrm { c } ) = 0.1093$, find $\mathrm { c }$.

Accepted Answer

A)  $- 1.23$ 
B)  $1.23$ 
C)  $0.4562$ 
D)  $0.27$ 
A)  $- 1.23$ 
B)  $1.23$ 
C)  $0.4562$ 
D)  $0.27$

Question 3

Solve the problem.
-In a population of 225 women, the heights of the women are normally distributed with a mean of 64.5 inches and a standard deviation of 2.9 inches. If 25 women are selected at random, find the probability that their mean height will exceed 66 inches. Assume that the sampling is done without replacement and use a finite population correction factor with N = 225.

Accepted Answer

A) 0.3015 
B) 0.0048 
C) 0.2912 
D) 0.0031 
A) 0.3015 
B) 0.0048 
C) 0.2912 
D) 0.0031

Question 4

Use the continuity correction and describe the region of the normal curve that corresponds to the indicated binomial probability.
-The probability of fewer than 43 democrats

Accepted Answer

A) The area to the left of 43 
B) The area to the left of 43.5 
C) The area to the right of 43.5 
D) The area to the left of 42.5 
A) The area to the left of 43 
B) The area to the left of 43.5 
C) The area to the right of 43.5 
D) The area to the left of 42.5

Question 5

Provide an appropriate response.
-Sketch a brief diagram of the standard normal distribution table. You only need to show two sets of values. Identify the z scores and the area scores in the table by circling the scores and writing z score and area by each one. Describe how to find the area corresponding to a given z score. Describe how to find the the z score corresponding to a given area value.

Accepted Answer

A quick sketch of a couple of values sho

Question 6

List the different possible samples, and find the mean of each of them
-Personal phone calls received in the last three days by a new employee were 3, 1, and 8. Assume that samples of size 2 are randomly selected with replacement from this population of three values.

Accepted Answer

Possible samples: 3-3; 3-1; 3-

Question 7

Solve the problem.
-A study of the amount of time it takes a mechanic to rebuild the transmission for a 1992 Chevrolet Cavalier shows that the mean is 8.4 hours and the standard deviation is 1.8 hours. If 40 mechanics are randomly selected, find the probability that their mean rebuild time exceeds 8.1 hours.

Accepted Answer

A) 0.8531 
B) 0.9146 
C) 0.7285 
D) 0.8457 
A) 0.8531 
B) 0.9146 
C) 0.7285 
D) 0.8457

Question 8

A poll of 1200 randomly selected students in grades 6 through 8 was conducted and found that 39% enjoy playing sports. What is the sampling distribution suggested by the given data?

Accepted Answer

It is the probability distribu

Question 9

A normal probability plot is given below for a sample of scores on an aptitude test. Use the plot to assess the normality of scores on this test. Explain your reasoning.

Accepted Answer

Since the normal probability p

Question 10

Construct a normal probability plot of the given data. Use your plot to determine whether the data come from a normally distributed population
-The ages of 30 students selected randomly from one college are as follows: $$\begin{array} { l l l l l } 
21 & 23 & 20 & 24 & 20 \
19 & 20 & 19 & 22 & 32 \
20 & 24 & 26 & 21 & 37 \
23 & 18 & 34 & 25 & 30 \
22 & 24 & 23 & 19 & 28 \
20 & 29 & 21 & 35 & 25 \
20 & 21 & 28 & 22 & 32
\end{array}$$

Accepted Answer

The requirement for normality

Question 11

Use the continuity correction and describe the region of the normal curve that corresponds to the indicated binomial probability.
-The probability of exactly 37 green marbles

Accepted Answer

A) The area between 36.5 and 37.5 
B) The area between 37 and 37.5 
C) The area between 36.5 and 37 
D) The area between 36.5 and 38.5 
A) The area between 36.5 and 37.5 
B) The area between 37 and 37.5 
C) The area between 36.5 and 37 
D) The area between 36.5 and 38.5

Question 12

Scores on a test have a mean of 62 and $\mathrm { Q } _ { 3 }$ is 84. The scores have a distribution that is approximately normal. Find the standard deviation. Round your answer to the nearest tenth.

Accepted Answer

A) 14.7 
B) 32.8 
C) 29.3 
D) 16.5 
A) 14.7 
B) 32.8 
C) 29.3 
D) 16.5

Question 13

The Precision Scientific Instrument Company manufactures thermometers that are supposed to give readings of 0°C at the freezing point of water. Tests on a large sample of these thermometers reveal that at the freezing point of water, some give readings below 0°C (denoted by negative numbers) and some give readings above 0°C (denoted by positive numbers). Assume that the mean reading is 0°C and the standard deviation of the readings is 1.00°C. Also assume that the frequency distribution of errors closely resembles the normal distribution. A thermometer is randomly selected and tested. Find the temperature reading corresponding to the given information.
-P(-0.73 < Z < 2.27)

Accepted Answer

A) 0.4884 
B) 0.7557 
C) 1.54 
D) 0.2211 
A) 0.4884 
B) 0.7557 
C) 1.54 
D) 0.2211

Question 14

Identify the probability of each sample, and describe the sampling distribution of the sample means.
-The number of books sold over the course of the four-day book fair were 189, 167, 271, and 83. Assume that samples of size 2 are randomly selected with replacement from this population of four values.

Accepted Answer

A)  $1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16$ 
B)  $1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16$ 
C)  $1 / 2 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 2 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 2 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 2 ; 1 / 16$ 
D)  $0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 1 / 16 ; 0 / 16 ; 1 / 8 ; 1 / 16 ; 1 / 16 ; 1 / 8 ; 1 / 16 ; 0 / 16 ; 1 / 8 ; 1 / 16$ 
A)  $1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16$ 
B)  $1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16 ; 1 / 16$ 
C)  $1 / 2 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 2 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 2 ; 1 / 16 ; 1 / 4 ; 1 / 16 ; 1 / 2 ; 1 / 16$ 
D)  $0 / 16 ; 1 / 16 ; 1 / 8 ; 0 / 16 ; 1 / 16 ; 1 / 8 ; 1 / 16 ; 0 / 16 ; 1 / 8 ; 1 / 16 ; 1 / 16 ; 1 / 8 ; 1 / 16 ; 0 / 16 ; 1 / 8 ; 1 / 16$

Question 15

If Z is a standard normal variable, find the probability
-The probability that Z lies between 0.7 and 1.98

Accepted Answer

A) 1.7341 
B) 0.2181 
C) 0.2175 
D) -0.2181 
A) 1.7341 
B) 0.2181 
C) 0.2175 
D) -0.2181

Question 16

Solve the problem.
-A final exam in Math 160 has a mean of 73 with standard deviation 7.8. If 24 students are randomly selected, find the probability that the mean of their test scores is less than 70.

Accepted Answer

A) 0.9699 
B) 0.0301 
C) 0.1006 
D) 0.0278 
A) 0.9699 
B) 0.0301 
C) 0.1006 
D) 0.0278

Question 17

Estimate the indicated probability by using the normal distribution as an approximation to the binomial distribution.
-n = 38 and p = .9

Accepted Answer

A) Normal approximation is suitable. 
B) Normal approximation is not suitable. 
A) Normal approximation is suitable. 
B) Normal approximation is not suitable.

Question 18

If Z is a standard normal variable, find the probability
-The probability that Z lies between -0.55 and 0.55

Accepted Answer

A) -0.9000 
B) -0.4176 
C) 0.9000 
D) 0.4176 
A) -0.9000 
B) -0.4176 
C) 0.9000 
D) 0.4176

Question 19

Find the probability that in 200 tosses of a fair die, we will obtain at most 30 fives.

Accepted Answer

A) .3229 
B) .2946 
C) .4936 
D) .1871 
A) .3229 
B) .2946 
C) .4936 
D) .1871

Question 20

Solve the problem.
-In one region, the September energy consumption levels for single-family homes are found to be normally distributed with a mean of 1050 kWh and a standard deviation of 218 kWh. If 50 different homes are randomly selected, find the probability that their mean energy consumption level for September is greater than 1075 kWh.

Accepted Answer

A) 0.2090 
B) 0.0438 
C) 0.2910 
D) 0.4562 
A) 0.2090 
B) 0.0438 
C) 0.2910 
D) 0.4562

For the binomial distribution with the given values for n and p -n = 12 and p = .5

Solve the problem. -Assume that $\mathrm { z }$ scores are normally distributed with a mean of 0 and a standard deviation of 1 . If $\mathrm { P } ( \mathrm { z } > \mathrm { c } ) = 0.1093$ , find $\mathrm { c }$ .

Use the continuity correction and describe the region of the normal curve that corresponds to the indicated binomial probability. -The probability of fewer than 43 democrats

List the different possible samples, and find the mean of each of them -Personal phone calls received in the last three days by a new employee were 3, 1, and 8. Assume that samples of size 2 are randomly selected with replacement from this population of three values.

A poll of 1200 randomly selected students in grades 6 through 8 was conducted and found that 39% enjoy playing sports. What is the sampling distribution suggested by the given data?

A normal probability plot is given below for a sample of scores on an aptitude test. Use the plot to assess the normality of scores on this test. Explain your reasoning.

Use the continuity correction and describe the region of the normal curve that corresponds to the indicated binomial probability. -The probability of exactly 37 green marbles

Scores on a test have a mean of 62 and $\mathrm { Q } _ { 3 }$ is 84. The scores have a distribution that is approximately normal. Find the standard deviation. Round your answer to the nearest tenth.

If Z is a standard normal variable, find the probability -The probability that Z lies between 0.7 and 1.98

Solve the problem. -A final exam in Math 160 has a mean of 73 with standard deviation 7.8. If 24 students are randomly selected, find the probability that the mean of their test scores is less than 70.

Estimate the indicated probability by using the normal distribution as an approximation to the binomial distribution. -n = 38 and p = .9

If Z is a standard normal variable, find the probability -The probability that Z lies between -0.55 and 0.55

Find the probability that in 200 tosses of a fair die, we will obtain at most 30 fives.

Introduction to Statistics

Summarizing and Graphing Data

Statistics for Describing, Exploring, and Comparing Data

Probability

Probability Distributions

Estimates and Sample Sizes

Hypothesis Testing

Inferences From Two Samples

Correlation and Regression

Multinomial Experiments and Contingency Tables

Analysis of Variance

Nonparametric Statistics

Statistical Process Control

Filters

Exam 6: Normal Probability Distributions

For the binomial distribution with the given values for n and p -n = 12 and p = .5

Solve the problem. -Assume that z\mathrm { z }z scores are normally distributed with a mean of 0 and a standard deviation of 1 . If P(z>c)=0.1093\mathrm { P } ( \mathrm { z } > \mathrm { c } ) = 0.1093P(z>c)=0.1093 , find c\mathrm { c }c .

Use the continuity correction and describe the region of the normal curve that corresponds to the indicated binomial probability. -The probability of fewer than 43 democrats

List the different possible samples, and find the mean of each of them -Personal phone calls received in the last three days by a new employee were 3, 1, and 8. Assume that samples of size 2 are randomly selected with replacement from this population of three values.

A poll of 1200 randomly selected students in grades 6 through 8 was conducted and found that 39% enjoy playing sports. What is the sampling distribution suggested by the given data?

A normal probability plot is given below for a sample of scores on an aptitude test. Use the plot to assess the normality of scores on this test. Explain your reasoning.

Use the continuity correction and describe the region of the normal curve that corresponds to the indicated binomial probability. -The probability of exactly 37 green marbles

Scores on a test have a mean of 62 and Q3\mathrm { Q } _ { 3 }Q3​ is 84. The scores have a distribution that is approximately normal. Find the standard deviation. Round your answer to the nearest tenth.

If Z is a standard normal variable, find the probability -The probability that Z lies between 0.7 and 1.98

Solve the problem. -A final exam in Math 160 has a mean of 73 with standard deviation 7.8. If 24 students are randomly selected, find the probability that the mean of their test scores is less than 70.

Estimate the indicated probability by using the normal distribution as an approximation to the binomial distribution. -n = 38 and p = .9

If Z is a standard normal variable, find the probability -The probability that Z lies between -0.55 and 0.55

Find the probability that in 200 tosses of a fair die, we will obtain at most 30 fives.

Introduction to Statistics

Summarizing and Graphing Data

Statistics for Describing, Exploring, and Comparing Data

Probability

Probability Distributions

Estimates and Sample Sizes

Hypothesis Testing

Inferences From Two Samples

Correlation and Regression

Multinomial Experiments and Contingency Tables

Analysis of Variance

Nonparametric Statistics

Statistical Process Control

Filters

Solve the problem. -Assume that $\mathrm { z }$ scores are normally distributed with a mean of 0 and a standard deviation of 1 . If $\mathrm { P } ( \mathrm { z } > \mathrm { c } ) = 0.1093$ , find $\mathrm { c }$ .

Scores on a test have a mean of 62 and $\mathrm { Q } _ { 3 }$ is 84. The scores have a distribution that is approximately normal. Find the standard deviation. Round your answer to the nearest tenth.