Question 1

If x is a binomial random variable with n = 10 and π = 0.8, the standard deviation of x is ___.

Accepted Answer

A)  8.0 
B)  1.26 
C)  1.60 
D)  64.0 
E)  10 
A)  8.0 
B)  1.26 
C)  1.60 
D)  64.0 
E)  10

Question 2

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 business faculty and 5 engineering faculty members. The probability that one business faculty and two engineering faculty are selected is approximately ___.

Accepted Answer

A)  0.15 
B)  0.06 
C)  0.33 
D)  0.48 
E)  0.58 
A)  0.15 
B)  0.06 
C)  0.33 
D)  0.48 
E)  0.58

Question 3

Aluminum castings are processed in lots of five each. A sample of two castings is randomly selected from each lot for inspection. A particular lot contains one defective casting; and x is the number of defective castings in the sample. P(x=1) is ___.

Accepted Answer

A)  0.2 
B)  0.4 
C)  0.6 
D)  0.8 
E)  1.0 
A)  0.2 
B)  0.4 
C)  0.6 
D)  0.8 
E)  1.0

Question 4

As in a binomial distribution, each trial of a hypergeometric distribution results in one of two mutually exclusive outcomes, i.e., either a success or a failure.

Accepted Answer

A) True 
 B)False

Question 5

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour. If the variable x = hourly wage has a discrete uniform distribution, what is the probability that a manager's wage is between $42 and $45?

Accepted Answer

P(x) = 1/16
P(42 < x

Question 6

For a discrete uniform distribution, if a = 4 and b = 5, what is P(x=10)?

Accepted Answer

A)  0.5 
B)  1.0 
C)  1.5 
D)  -0.5 
E)  -1.0 
A)  0.5 
B)  1.0 
C)  1.5 
D)  -0.5 
E)  -1.0

Question 7

The probabilities that a student wins $50,000, $20,000 or $12,000 are 0.7, 0.2 and 0.1 respectively. The expected value of the random x = win is approximately.

Accepted Answer

A)  $37,800. 
B)  $40,200. 
C)  -$37,800. 
D)  -$40,200. 
E)  0. 
A)  $37,800. 
B)  $40,200. 
C)  -$37,800. 
D)  -$40,200. 
E)  0.

Question 8

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 business faculty and 5 engineering faculty members. The probability that all three faculty selected are all in business is approximately ___.

Accepted Answer

A)  0.05 
B)  0.33 
C)  0.11 
D)  0.80 
E)  0.90 
A)  0.05 
B)  0.33 
C)  0.11 
D)  0.80 
E)  0.90

Question 9

A large industrial firm allows a discount on any invoice that is paid within 30 days. Of all invoices, 10% receive the discount. In a company audit, 15 invoices are sampled at random. The mean (average) value of the number of the 15 sampled invoices that receive discount is ___.

Accepted Answer

A)  1 
B)  3 
C)  1.5 
D)  2 
E)  10 
A)  1 
B)  3 
C)  1.5 
D)  2 
E)  10

Question 10

For the Poisson distribution the mean and the variance are the same.

Accepted Answer

A) True 
 B)False

Question 11

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour (salaries are always to the nearest dollar). If the variable x = hourly wage has a discrete uniform distribution, what is the probability that a manager's wage is between $42 and $45?

Accepted Answer

A)  0.50 
B)  0.35 
C)  0.30 
D)  0.25 
E)  0.13 
A)  0.50 
B)  0.35 
C)  0.30 
D)  0.25 
E)  0.13

Question 12

Dorothy Little purchased a mailing list of 2,000 names and addresses for her mail order business, but after scanning the list she doubts the authenticity of the list. She randomly selects five names from the list for validation. If 40% of the names on the list are non-authentic, and x is the number on non-authentic names in her sample, the expected (mean) value of x is ___.

Accepted Answer

A)  2.50 
B)  2.00 
C)  1.50 
D)  1.25 
E)  1.35 
A)  2.50 
B)  2.00 
C)  1.50 
D)  1.25 
E)  1.35

Question 13

The probability distribution for the daily demand of laptops at a local store is shown below. In this distribution, the random variable x is the daily demand of laptops:   Which of the following statements is true?

Accepted Answer

A)  This distribution is skewed to the right. 
B)  This is a binomial distribution. 
C)  This is a normal distribution. 
D)  This distribution is skewed to the left. 
E)  This distribution is bimodal. 
A)  This distribution is skewed to the right. 
B)  This is a binomial distribution. 
C)  This is a normal distribution. 
D)  This distribution is skewed to the left. 
E)  This distribution is bimodal.

Question 14

If x is a binomial random variable with n = 10 and π = 0.8, what is the probability that x is equal to 4?

Accepted Answer

A) .0055 
B) .0063 
C) .124 
D) .232 
E) .994 
A) .0055 
B) .0063 
C) .124 
D) .232 
E) .994

Question 15

A basketball player makes 80% of her free throws. Suppose this probability is the same for each free throw she attempts. The probability that she doesn't make a free throw until her fifth attempt this season is

Accepted Answer

A)  0.32768. 
B)  0.08192. 
C)  0.00128. 
D)  0.00032. 
E)  0.00004. 
A)  0.32768. 
B)  0.08192. 
C)  0.00128. 
D)  0.00032. 
E)  0.00004.

Question 16

Ten policyholders file claims with CareFree Insurance. Three of these claims are fraudulent. Claims manager Earl Evans randomly selects three of the ten claims for thorough investigation. If x represents the number of fraudulent claims in Earl's sample, P(x=0) is ___.

Accepted Answer

A)  0.0083 
B)  0.3430 
C)  0.0000 
D)  0.2917 
E)  0.8917 
A)  0.0083 
B)  0.3430 
C)  0.0000 
D)  0.2917 
E)  0.8917

Question 17

In a certain communications system, there is an average of 1 transmission error per 10 seconds. Assume that the distribution of transmission errors is Poisson. The probability of 1 error in a period of one-half minute is approximately ___

Accepted Answer

A)  0.1493 
B)  0.3333 
C)  0.3678 
D)  0.1336 
E)  0.03 
A)  0.1493 
B)  0.3333 
C)  0.3678 
D)  0.1336 
E)  0.03

Question 18

Poisson distribution describes the occurrence of discrete events that may occur over a continuous interval of time or space.

Accepted Answer

A) True 
 B)False

Question 19

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour (salaries are always to the nearest dollar). If the variable x = hourly wage has a discrete uniform distribution, what is the mean wage for the managers?

Accepted Answer

A)  $28.33 
B)  $35.00 
C)  $37.50 
D)  $42.50 
E)  $50.00 
A)  $28.33 
B)  $35.00 
C)  $37.50 
D)  $42.50 
E)  $50.00

Question 20

You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table:   Which of the following statements is true?

Accepted Answer

A)  This distribution is skewed to the right. 
B)  This is a binomial distribution. 
C)  This distribution is symmetric. 
D)  This distribution is skewed to the left. 
E)  This is a Poisson distribution. 
A)  This distribution is skewed to the right. 
B)  This is a binomial distribution. 
C)  This distribution is symmetric. 
D)  This distribution is skewed to the left. 
E)  This is a Poisson distribution.

If x is a binomial random variable with n = 10 and π = 0.8, the standard deviation of x is ___.

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 business faculty and 5 engineering faculty members. The probability that one business faculty and two engineering faculty are selected is approximately ___.

Aluminum castings are processed in lots of five each. A sample of two castings is randomly selected from each lot for inspection. A particular lot contains one defective casting; and x is the number of defective castings in the sample. P(x=1) is ___.

As in a binomial distribution, each trial of a hypergeometric distribution results in one of two mutually exclusive outcomes, i.e., either a success or a failure.

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour. If the variable x = hourly wage has a discrete uniform distribution, what is the probability that a manager's wage is between $42 and $45?

For a discrete uniform distribution, if a = 4 and b = 5, what is P(x=10)?

The probabilities that a student wins $50,000, $20,000 or $12,000 are 0.7, 0.2 and 0.1 respectively. The expected value of the random x = win is approximately.

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 business faculty and 5 engineering faculty members. The probability that all three faculty selected are all in business is approximately ___.

A large industrial firm allows a discount on any invoice that is paid within 30 days. Of all invoices, 10% receive the discount. In a company audit, 15 invoices are sampled at random. The mean (average) value of the number of the 15 sampled invoices that receive discount is ___.

For the Poisson distribution the mean and the variance are the same.

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour (salaries are always to the nearest dollar). If the variable x = hourly wage has a discrete uniform distribution, what is the probability that a manager's wage is between $42 and $45?

The probability distribution for the daily demand of laptops at a local store is shown below. In this distribution, the random variable x is the daily demand of laptops: Which of the following statements is true?

If x is a binomial random variable with n = 10 and π = 0.8, what is the probability that x is equal to 4?

A basketball player makes 80% of her free throws. Suppose this probability is the same for each free throw she attempts. The probability that she doesn't make a free throw until her fifth attempt this season is

Ten policyholders file claims with CareFree Insurance. Three of these claims are fraudulent. Claims manager Earl Evans randomly selects three of the ten claims for thorough investigation. If x represents the number of fraudulent claims in Earl's sample, P(x=0) is ___.

In a certain communications system, there is an average of 1 transmission error per 10 seconds. Assume that the distribution of transmission errors is Poisson. The probability of 1 error in a period of one-half minute is approximately ___

Poisson distribution describes the occurrence of discrete events that may occur over a continuous interval of time or space.

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour (salaries are always to the nearest dollar). If the variable x = hourly wage has a discrete uniform distribution, what is the mean wage for the managers?

You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table: Which of the following statements is true?

Introduction to Statistics

Organizing and Visualizing Data

Descriptive Statistics

Gathering Data

Probability

Decision Analysis and Expected Value

Continuous Distributions

Sampling Distributions

Confidence Intervals

Hypothesis Testing for Single Populations

Hypothesis Testing for Two Populations

Analysis of Variance Anova

Linear Correlation and Simple Linear Regression Analysis

Categorical Versus Categorical: Tests

Filters

Exam 7: Discrete Probability Distributions

If x is a binomial random variable with n = 10 and π = 0.8, the standard deviation of x is ___.

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 business faculty and 5 engineering faculty members. The probability that one business faculty and two engineering faculty are selected is approximately ___.

Aluminum castings are processed in lots of five each. A sample of two castings is randomly selected from each lot for inspection. A particular lot contains one defective casting; and x is the number of defective castings in the sample. P(x=1) is ___.

As in a binomial distribution, each trial of a hypergeometric distribution results in one of two mutually exclusive outcomes, i.e., either a success or a failure.

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour. If the variable x = hourly wage has a discrete uniform distribution, what is the probability that a manager's wage is between $42 and $45?

For a discrete uniform distribution, if a = 4 and b = 5, what is P(x=10)?

The probabilities that a student wins $50,000, $20,000 or $12,000 are 0.7, 0.2 and 0.1 respectively. The expected value of the random x = win is approximately.

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 business faculty and 5 engineering faculty members. The probability that all three faculty selected are all in business is approximately ___.

A large industrial firm allows a discount on any invoice that is paid within 30 days. Of all invoices, 10% receive the discount. In a company audit, 15 invoices are sampled at random. The mean (average) value of the number of the 15 sampled invoices that receive discount is ___.

For the Poisson distribution the mean and the variance are the same.

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour (salaries are always to the nearest dollar). If the variable x = hourly wage has a discrete uniform distribution, what is the probability that a manager's wage is between $42 and $45?

The probability distribution for the daily demand of laptops at a local store is shown below. In this distribution, the random variable x is the daily demand of laptops: Which of the following statements is true?

If x is a binomial random variable with n = 10 and π = 0.8, what is the probability that x is equal to 4?

A basketball player makes 80% of her free throws. Suppose this probability is the same for each free throw she attempts. The probability that she doesn't make a free throw until her fifth attempt this season is

Ten policyholders file claims with CareFree Insurance. Three of these claims are fraudulent. Claims manager Earl Evans randomly selects three of the ten claims for thorough investigation. If x represents the number of fraudulent claims in Earl's sample, P(x=0) is ___.

In a certain communications system, there is an average of 1 transmission error per 10 seconds. Assume that the distribution of transmission errors is Poisson. The probability of 1 error in a period of one-half minute is approximately ___

Poisson distribution describes the occurrence of discrete events that may occur over a continuous interval of time or space.

At A-Life Corporation, managers begin at $35/hour until they reach $50/hour (salaries are always to the nearest dollar). If the variable x = hourly wage has a discrete uniform distribution, what is the mean wage for the managers?

You are offered an investment opportunity. Its outcomes and probabilities are presented in the following table: Which of the following statements is true?

Introduction to Statistics

Organizing and Visualizing Data

Descriptive Statistics

Gathering Data

Probability

Decision Analysis and Expected Value

Continuous Distributions

Sampling Distributions

Confidence Intervals

Hypothesis Testing for Single Populations

Hypothesis Testing for Two Populations

Analysis of Variance Anova

Linear Correlation and Simple Linear Regression Analysis

Categorical Versus Categorical: Tests

Filters