Question 1

Does the following table describe a discrete probability distribution?

Accepted Answer

No, the sum of proba

Question 2

There are currently 18 pit bulls at the pound. Of the 18 pit bulls, four have attacked another dog in the last year. Joe, a member of the staff, randomly selects six of the pit bulls for his group. What is the probability that exactly one of the pit bulls in Joe's group attacked another dog last year?

Accepted Answer

A)  0.1618 
B)  0.3235 
C)  0.4314 
D)  0.4853 
A)  0.1618 
B)  0.3235 
C)  0.4314 
D)  0.4853

Question 3

According to the Mortgage Bankers Association, 8% of U.S. mortgages were delinquent last year. A delinquent mortgage is one that has missed at least one payment but has not yet gone to foreclosure. A random sample of eight mortgages was selected. What is the probability that fewer than three of these mortgages are delinquent?

Accepted Answer

A)  0.7018 
B)  0.7583 
C)  0.9789 
D)  0.8225 
A)  0.7018 
B)  0.7583 
C)  0.9789 
D)  0.8225

Question 4

Chauncey Billups, a current shooting guard for the Los Angeles Clippers, has a career free-throw percentage of 89.4%. Suppose he shoots six free throws in tonight's game. What is the probability that Billups makes five or more of his free throws?

Accepted Answer

A)  0.3632 
B)  0.5105 
C)  0.8737 
D)  0.8940 
A)  0.3632 
B)  0.5105 
C)  0.8737 
D)  0.8940

Question 5

Suppose your firm is buying five new computers. The manufacturer offers a warranty to replace any computer that breaks down within three years. Suppose there is a 25% chance that any given computer breaks down within three years.
A) What is the probability that exactly one of the computers breaks down within five years?
B) What is the probability that at least one of the computers breaks down within five years?
C) Suppose the warranty for five computers costs $700, while a new computer costs $600. Is the warranty less expensive than the expected cost of replacing the broken computers?

Accepted Answer

a. 0.3955

Question 6

It is known that 10% of the calculators shipped from a particular factory are defective. What is the probability that exactly three of five chosen calculators are defective?

Accepted Answer

A)  0.00729 
B)  0.0081 
C)  0.081 
D)  0.03 
A)  0.00729 
B)  0.0081 
C)  0.081 
D)  0.03

Question 7

An investor has a $100,000 portfolio of which $75,000 has been invested in Stock A and the remainder in Stock B. Other characteristics of the portfolio are shown in the accompanying table.   The standard deviation of the portfolio is ________.

Accepted Answer

A)  9.39 (%) 
B)  14.19 (%). 
C)  88.23 (%)2. 
D)  201.41 (%)2. 
A)  9.39 (%) 
B)  14.19 (%). 
C)  88.23 (%)2. 
D)  201.41 (%)2.

Question 8

A bank manager estimates that an average of two customers enters the tellers' queue every five minutes. Assume that the number of customers that enters the tellers' queue is Poisson distributed. What is the probability that exactly seven customers enter the queue in a randomly selected 15-minute period?

Accepted Answer

A)  0.0034 
B)  0.1033 
C)  0.1377 
D)  0.1606 
A)  0.0034 
B)  0.1033 
C)  0.1377 
D)  0.1606

Question 9

We use the hypergeometric distribution in place of the binomial distribution when we are sampling with replacement from a population whose size N is significantly larger than the sample size n.

Accepted Answer

A) True 
 B)False

Question 10

For a particular clothing store, a marketing firm finds that 16% of $10-off coupons delivered by mail are redeemed. Suppose six customers are randomly selected and are mailed $10-off coupons. What is the probability that at least two of the customers redeem the coupon?

Accepted Answer

A)  0.2472 
B)  0.3513 
C)  0.4015 
D)  0.7528 
A)  0.2472 
B)  0.3513 
C)  0.4015 
D)  0.7528

Question 11

Four of your students submitted an entry to a writing contest. A total of 24 entries were submitted. Six of the entries will move on to the next round.
A) What is the probability that all four of your students will move on to the next round?
B) How many of your students are expected to move to the next round?
C) What is the probability that fewer of your students than expected will make it to the next round than expected?
D) What is the standard deviation of the number of students expected to move on to the next round.

Accepted Answer

a. 0.0014

Question 12

The variance of a random variable X provides us with a measure of central location of the distribution of X.

Accepted Answer

A) True 
 B)False

Question 13

A risk-averse consumer demands a(n) ________ expected gain as compensation for taking risk.

Accepted Answer

The answer of A risk-averse consumer demands a(n) ________ expected...

Question 14

You are attending a baseball game with two family members when it is announced that four fans in your section (which holds 20 spectators total) will win a free autographed baseball.
A) What is the probability that at least one member of your family (including yourself) wins an autographed baseball?
B) What is the probability that two members of your family win an autographed baseball?
C) What is the probability that all three of you win an autographed baseball?

Accepted Answer

a. 0.5088

Question 15

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year.   The expected value and the variance of this distribution are ________ and ________.

Accepted Answer

A)  Option A 
B)  Option B 
C)  Option C 
D)  Option D 
A)  Option A 
B)  Option B 
C)  Option C 
D)  Option D

Question 16

An urn contains 12 balls, five of which are red. Selection of a red ball is desired and is therefore considered to be a success. If three balls are selected, what is the expected value of the distribution of the number of selected red balls?

Accepted Answer

A)  0.4167 
B)  0.8333 
C)  0.5833 
D)  1.2500 
A)  0.4167 
B)  0.8333 
C)  0.5833 
D)  1.2500

Question 17

For a particular clothing store, a marketing firm finds that 16% of $10-off coupons delivered by mail are redeemed. Suppose six customers are randomly selected and are mailed $10-off coupons. What is the probability that no more than one of the customers redeems the coupon?

Accepted Answer

A)  0.2472 
B)  0.3513 
C)  0.4015 
D)  0.7528 
A)  0.2472 
B)  0.3513 
C)  0.4015 
D)  0.7528

Question 18

Which of the following statements is the most accurate about a Poisson random variable?

Accepted Answer

A)  It counts the number of successes in a given number of trials. 
B)  It counts the number of successes in a specified time or space interval. 
C)  It is a continuous random variable. 
D)  It has a bell-shaped distribution. 
A)  It counts the number of successes in a given number of trials. 
B)  It counts the number of successes in a specified time or space interval. 
C)  It is a continuous random variable. 
D)  It has a bell-shaped distribution.

Question 19

An investor has an $80,000 portfolio of which $60,000 has been invested in Stock A and the remainder in Stock B. Other characteristics of the portfolio are as follows:   a. Calculate the correlation coefficient.
B) Calculate the expected return of the portfolio.
C) Calculate the standard deviation of the portfolio.

Accepted Answer

a. -0.06
b

Question 20

According to geologists, the San Francisco Bay Area experiences five earthquakes with a magnitude of 6.5 or greater every 100 years. What is the standard deviation of the number of earthquakes with a magnitude of 6.5 or greater striking the San Francisco Bay Area in the next 40 years?

Accepted Answer

A)  1.414 
B)  2.000 
C)  2.236 
D)  5.000 
A)  1.414 
B)  2.000 
C)  2.236 
D)  5.000

Does the following table describe a discrete probability distribution?

Chauncey Billups, a current shooting guard for the Los Angeles Clippers, has a career free-throw percentage of 89.4%. Suppose he shoots six free throws in tonight's game. What is the probability that Billups makes five or more of his free throws?

It is known that 10% of the calculators shipped from a particular factory are defective. What is the probability that exactly three of five chosen calculators are defective?

An investor has a $100,000 portfolio of which $75,000 has been invested in Stock A and the remainder in Stock B. Other characteristics of the portfolio are shown in the accompanying table. The standard deviation of the portfolio is ________.

We use the hypergeometric distribution in place of the binomial distribution when we are sampling with replacement from a population whose size N is significantly larger than the sample size n.

For a particular clothing store, a marketing firm finds that 16% of $10-off coupons delivered by mail are redeemed. Suppose six customers are randomly selected and are mailed $10-off coupons. What is the probability that at least two of the customers redeem the coupon?

The variance of a random variable X provides us with a measure of central location of the distribution of X.

A risk-averse consumer demands a(n) ________ expected gain as compensation for taking risk.

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year. The expected value and the variance of this distribution are and .

An urn contains 12 balls, five of which are red. Selection of a red ball is desired and is therefore considered to be a success. If three balls are selected, what is the expected value of the distribution of the number of selected red balls?

For a particular clothing store, a marketing firm finds that 16% of $10-off coupons delivered by mail are redeemed. Suppose six customers are randomly selected and are mailed $10-off coupons. What is the probability that no more than one of the customers redeems the coupon?

Which of the following statements is the most accurate about a Poisson random variable?

According to geologists, the San Francisco Bay Area experiences five earthquakes with a magnitude of 6.5 or greater every 100 years. What is the standard deviation of the number of earthquakes with a magnitude of 6.5 or greater striking the San Francisco Bay Area in the next 40 years?

Statistics and Data

Tabular and Graphical Methods

Numerical Descriptive Measures

Introduction to Probability

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Testing

Statistical Inference Concerning Two Populations

Statistical Inference Concerning Variance

Chi-Square Tests

Analysis of Variance

Regression Analysis

Inference With Regression Models

Regression Models for Nonlinear Relationships

Regression Models With Dummy Variables

Time Series and Forecasting

Returns, Index Numbers, and Inflation

Nonparametric Tests

Filters

Exam 5: Discrete Probability Distributions

Does the following table describe a discrete probability distribution?

Chauncey Billups, a current shooting guard for the Los Angeles Clippers, has a career free-throw percentage of 89.4%. Suppose he shoots six free throws in tonight's game. What is the probability that Billups makes five or more of his free throws?

It is known that 10% of the calculators shipped from a particular factory are defective. What is the probability that exactly three of five chosen calculators are defective?

An investor has a $100,000 portfolio of which $75,000 has been invested in Stock A and the remainder in Stock B. Other characteristics of the portfolio are shown in the accompanying table. The standard deviation of the portfolio is ________.

We use the hypergeometric distribution in place of the binomial distribution when we are sampling with replacement from a population whose size N is significantly larger than the sample size n.

For a particular clothing store, a marketing firm finds that 16% of $10-off coupons delivered by mail are redeemed. Suppose six customers are randomly selected and are mailed $10-off coupons. What is the probability that at least two of the customers redeem the coupon?

The variance of a random variable X provides us with a measure of central location of the distribution of X.

A risk-averse consumer demands a(n) ________ expected gain as compensation for taking risk.

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year. The expected value and the variance of this distribution are ________ and ________.

An urn contains 12 balls, five of which are red. Selection of a red ball is desired and is therefore considered to be a success. If three balls are selected, what is the expected value of the distribution of the number of selected red balls?

For a particular clothing store, a marketing firm finds that 16% of $10-off coupons delivered by mail are redeemed. Suppose six customers are randomly selected and are mailed $10-off coupons. What is the probability that no more than one of the customers redeems the coupon?

Which of the following statements is the most accurate about a Poisson random variable?

According to geologists, the San Francisco Bay Area experiences five earthquakes with a magnitude of 6.5 or greater every 100 years. What is the standard deviation of the number of earthquakes with a magnitude of 6.5 or greater striking the San Francisco Bay Area in the next 40 years?

Statistics and Data

Tabular and Graphical Methods

Numerical Descriptive Measures

Introduction to Probability

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Testing

Statistical Inference Concerning Two Populations

Statistical Inference Concerning Variance

Chi-Square Tests

Analysis of Variance

Regression Analysis

Inference With Regression Models

Regression Models for Nonlinear Relationships

Regression Models With Dummy Variables

Time Series and Forecasting

Returns, Index Numbers, and Inflation

Nonparametric Tests

Filters

An analyst has constructed the following probability distribution for firm X's predicted return for the upcoming year. The expected value and the variance of this distribution are and .