Question 1

A weighted average of the value of a random variable, where the probability function provides weights is known as

Accepted Answer

A) a probability function 
B) a random variable 
C) the expected value 
D) None of the answers is correct 
A) a probability function 
B) a random variable 
C) the expected value 
D) None of the answers is correct

Question 2

Assume that you have a binomial experiment with p = 0.4 and a sample size of 50. The variance of this distribution is

Accepted Answer

A) 20 
B) 12 
C) 3.46 
D) Not enough information is given to answer this question. 
A) 20 
B) 12 
C) 3.46 
D) Not enough information is given to answer this question.

Question 3

The expected value of a random variable is the

Accepted Answer

A) value of the random variable that should be observed on the next repeat of the experiment 
B) value of the random variable that occurs most frequently 
C) square root of the variance 
D) None of the answers is correct. 
A) value of the random variable that should be observed on the next repeat of the experiment 
B) value of the random variable that occurs most frequently 
C) square root of the variance 
D) None of the answers is correct.

Question 4

When using Excel's BINOM.DIST function, one should choose TRUE for the fourth input if

Accepted Answer

A) a probability is desired 
B) a cumulative probability is desired 
C) the expected value is desired 
D) the correct answer is desired 
A) a probability is desired 
B) a cumulative probability is desired 
C) the expected value is desired 
D) the correct answer is desired

Question 5

Exhibit 5-6
Probability Distribution  
-Refer to Exhibit 5-6. The expected value of x equals

Accepted Answer

A) 24 
B) 25 
C) 30 
D) 100 
A) 24 
B) 25 
C) 30 
D) 100

Question 6

Excel's BINOM.DIST function can be used to compute

Accepted Answer

A) bin width for histograms 
B) binomial probabilities 
C) cumulative binomial probabilities 
D) both binomial probabilities and cumulative binomial probabilities are correct. 
A) bin width for histograms 
B) binomial probabilities 
C) cumulative binomial probabilities 
D) both binomial probabilities and cumulative binomial probabilities are correct.

Question 7

Exhibit 5-10
The probability that Pete will catch fish on a particular day when he goes fishing is 0.8. Pete is going fishing 3 days next week.
-Refer to Exhibit 5-10. The variance of the number of days Pete will catch fish is

Accepted Answer

A) .16 
B) .48 
C) .8 
D) 2.4 
A) .16 
B) .48 
C) .8 
D) 2.4

Question 8

John parks cars at a hotel. On the average, 6.7 cars will arrive in an hour. Assume that a driver's decision on whether to let John park the car does not depend upon any other person's decision. Define the random variable x to be the number of cars arriving in any hour period.
a.What is the appropriate probability distribution for x? Explain how x satisfies the properties of the distribution.
b.Compute the probability that exactly 5 cars will arrive in the next hour.
c.Compute the probability that no more than 5 cars will arrive in the next hour.

Accepted Answer

a.Poisson

Question 9

Exhibit 5-9
Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected.
-Refer to Exhibit 5-9. The probability that the sample contains 2 female voters is

Accepted Answer

A) 0.0778 
B) 0.7780 
C) 0.5000 
D) 0.3456 
A) 0.0778 
B) 0.7780 
C) 0.5000 
D) 0.3456

Question 10

The probability distribution of the daily demand for a product is shown below.   
a.What is the expected number of units demanded per day?
b.Determine the variance and the standard deviation.

Accepted Answer

a.3.05
b.v

Question 11

Exhibit 5-7
A sample of 2,500 people was asked how many cups of coffee they drink in the morning. You are given the following sample information.  
-In a binomial experiment, the

Accepted Answer

A) probability of success does not change from trial to trial 
B) probability of success does change from trial to trial 
C) probability of success could change from trial to trial, depending on the situation under consideration 
D) All of these answers are correct. 
A) probability of success does not change from trial to trial 
B) probability of success does change from trial to trial 
C) probability of success could change from trial to trial, depending on the situation under consideration 
D) All of these answers are correct.

Question 12

In a large university, 75% of students live in the dormitories. A random sample of 5 students is selected.
a.Define the random variable in words for this experiment.
b.What is the probability that the sample contains exactly three students who live in the dormitories?
c.What is the probability that the sample contains no students who live in the dormitories?
d.What is the probability that the sample contains more than three students who do not live in the dormitories?
e.What is the expected number of students (in the sample) who do not live in the dormitories?

Accepted Answer

a.x = the number of

Question 13

General Hospital has noted that they admit an average of 8 patients per hour.
a.Define the random variable in words for this experiment.
b.What is the probability that during the next hour fewer than 3 patients will be admitted?
c.What is the probability that during the next two hours exactly 8 patients will be admitted?

Accepted Answer

a.x = the number of

Question 14

A production process produces 2% defective parts. A sample of five parts from the production process is selected. What is the probability that the sample contains exactly two defective parts?

Accepted Answer

A) 0.0004 
B) 0.0038 
C) 0.10 
D) 0.02 
A) 0.0004 
B) 0.0038 
C) 0.10 
D) 0.02

Question 15

Bivariate probabilities are often called

Accepted Answer

A) union probabilities 
B) conditional probabilities 
C) marginal probabilities 
D) joint probabilities 
A) union probabilities 
B) conditional probabilities 
C) marginal probabilities 
D) joint probabilities

Question 16

The probability distribution for the rate of return on an investment is   
a.What is the probability that the rate of return will be at least 10%?
b.What is the expected rate of return?
c.What is the variance of the rate of return?

Accepted Answer

a.0.7
b.10

Question 17

Exhibit 5-6
Probability Distribution  
-Refer to Exhibit 5-6. The variance of x equals

Accepted Answer

A) 9.165 
B) 84 
C) 85 
D) 93.33 
A) 9.165 
B) 84 
C) 85 
D) 93.33

Question 18

A numerical description of the outcome of an experiment is called a

Accepted Answer

A) descriptive statistic 
B) probability function 
C) variance 
D) random variable 
A) descriptive statistic 
B) probability function 
C) variance 
D) random variable

Question 19

The probability function for the number of insurance policies John will sell to a customer is given by
f(x) = .5 - (x/6) for x = 0, 1, or 2
a.Is this a valid probability function? Explain your answer.
b.What is the probability that John will sell exactly 2 policies to a customer?
c.What is the probability that John will sell at least 2 policies to a customer?
d.What is the expected number of policies John will sell?
e.What is the variance of the number of policies John will sell?

Accepted Answer

a.yes f(x) @#LAT-DLM& 0 and  @#LAT-DLM&f

Question 20

Exhibit 5-5
AMR is a computer-consulting firm. The number of new clients that they have obtained each month has ranged from 0 to 6. The number of new clients has the probability distribution that is shown below.  
-Refer to Exhibit 5-5. The standard deviation is

Accepted Answer

A) 1.431 
B) 2.047 
C) 3.05 
D) 21 
A) 1.431 
B) 2.047 
C) 3.05 
D) 21

A weighted average of the value of a random variable, where the probability function provides weights is known as

Assume that you have a binomial experiment with p = 0.4 and a sample size of 50. The variance of this distribution is

The expected value of a random variable is the

When using Excel's BINOM.DIST function, one should choose TRUE for the fourth input if

Exhibit 5-6 Probability Distribution -Refer to Exhibit 5-6. The expected value of x equals

Excel's BINOM.DIST function can be used to compute

Exhibit 5-10 The probability that Pete will catch fish on a particular day when he goes fishing is 0.8. Pete is going fishing 3 days next week. -Refer to Exhibit 5-10. The variance of the number of days Pete will catch fish is

Exhibit 5-9 Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected. -Refer to Exhibit 5-9. The probability that the sample contains 2 female voters is

The probability distribution of the daily demand for a product is shown below. a.What is the expected number of units demanded per day? b.Determine the variance and the standard deviation.

Exhibit 5-7 A sample of 2,500 people was asked how many cups of coffee they drink in the morning. You are given the following sample information. -In a binomial experiment, the

A production process produces 2% defective parts. A sample of five parts from the production process is selected. What is the probability that the sample contains exactly two defective parts?

Bivariate probabilities are often called

The probability distribution for the rate of return on an investment is a.What is the probability that the rate of return will be at least 10%? b.What is the expected rate of return? c.What is the variance of the rate of return?

Exhibit 5-6 Probability Distribution -Refer to Exhibit 5-6. The variance of x equals

A numerical description of the outcome of an experiment is called a

Exhibit 5-5 AMR is a computer-consulting firm. The number of new clients that they have obtained each month has ranged from 0 to 6. The number of new clients has the probability distribution that is shown below. -Refer to Exhibit 5-5. The standard deviation is

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit, Independence and Multiple Proportions

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Decision Analysis

Sample Survey

Filters

Exam 5: Discrete Probability Distributions

A weighted average of the value of a random variable, where the probability function provides weights is known as

Assume that you have a binomial experiment with p = 0.4 and a sample size of 50. The variance of this distribution is

The expected value of a random variable is the

When using Excel's BINOM.DIST function, one should choose TRUE for the fourth input if

Exhibit 5-6 Probability Distribution -Refer to Exhibit 5-6. The expected value of x equals

Excel's BINOM.DIST function can be used to compute

Exhibit 5-10 The probability that Pete will catch fish on a particular day when he goes fishing is 0.8. Pete is going fishing 3 days next week. -Refer to Exhibit 5-10. The variance of the number of days Pete will catch fish is

Exhibit 5-9 Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected. -Refer to Exhibit 5-9. The probability that the sample contains 2 female voters is

The probability distribution of the daily demand for a product is shown below. a.What is the expected number of units demanded per day? b.Determine the variance and the standard deviation.

Exhibit 5-7 A sample of 2,500 people was asked how many cups of coffee they drink in the morning. You are given the following sample information. -In a binomial experiment, the

A production process produces 2% defective parts. A sample of five parts from the production process is selected. What is the probability that the sample contains exactly two defective parts?

Bivariate probabilities are often called

The probability distribution for the rate of return on an investment is a.What is the probability that the rate of return will be at least 10%? b.What is the expected rate of return? c.What is the variance of the rate of return?

Exhibit 5-6 Probability Distribution -Refer to Exhibit 5-6. The variance of x equals

A numerical description of the outcome of an experiment is called a

Exhibit 5-5 AMR is a computer-consulting firm. The number of new clients that they have obtained each month has ranged from 0 to 6. The number of new clients has the probability distribution that is shown below. -Refer to Exhibit 5-5. The standard deviation is

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit, Independence and Multiple Proportions

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Decision Analysis

Sample Survey

Filters