Question 1

A measure of the average value of a random variable is called an)

Accepted Answer

A)  variance 
B)  standard deviation 
C)  expected value 
D)  coefficient of variation 
A)  variance 
B)  standard deviation 
C)  expected value 
D)  coefficient of variation

Question 2

Exhibit 5-4
Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected.
-Refer to Exhibit 5-4. The probability that there are no females in the sample 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 3

Exhibit 5-1
The following represents the probability distribution for the daily demand of computers at a local store.
 $$\begin{array} { c c } 
\text { Demand } & \text { Probability } \
0 & 0.1 \
1 & 0.2 \
2 & 0.3 \
3 & 0.2 \
4 & 0 ?
\end{array}$$
-Refer to Exhibit 5-1. The probability of having a demand for at least two computers is

Accepted Answer

A)  0.7 
B)  0.3 
C)  0.4 
D)  1.0 
A)  0.7 
B)  0.3 
C)  0.4 
D)  1.0

Question 4

Exhibit 5-5
Probability Distribution
 $\begin{array}{ll}x&fx)\
10 & .2 \
20 & .3 \
30 & .4 \
40 & .1
\end{array}$
-Refer to Exhibit 5-5. 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 5

The standard deviation is the

Accepted Answer

A)  variance squared 
B)  square root of the sum of the deviations from the mean 
C)  same as the expected value 
D)  positive square root of the variance 
A)  variance squared 
B)  square root of the sum of the deviations from the mean 
C)  same as the expected value 
D)  positive square root of the variance

Question 6

A continuous random variable may assume

Accepted Answer

A)  any value in an interval or collection of intervals 
B)  only integer values in an interval or collection of intervals 
C)  only fractional values in an interval or collection of intervals 
D)  only the positive integer values in an interval 
A)  any value in an interval or collection of intervals 
B)  only integer values in an interval or collection of intervals 
C)  only fractional values in an interval or collection of intervals 
D)  only the positive integer values in an interval

Question 7

A description of the distribution of the values of a random variable and their associated probabilities is called a

Accepted Answer

A)  probability distribution 
B)  random variance 
C)  random variable 
D)  expected value 
A)  probability distribution 
B)  random variance 
C)  random variable 
D)  expected value

Question 8

Exhibit 5-7
The probability that Pete will catch fish when he goes fishing is .8. Pete is going to fish 3 days next week. Define the random variable X to be the number of days Pete catches fish.
-Refer to Exhibit 5-7. The probability that Pete will catch fish on one day or less is

Accepted Answer

A)  .008 
B)  .096 
C)  .104 
D)  .8 
A)  .008 
B)  .096 
C)  .104 
D)  .8

Question 9

A retailer of electronic equipment received six VCRs from the manufacturer. Three of the VCRs were damaged in the shipment. The retailer sold two VCRs to two customers.
a. Can a binomial formula be used for the solution of the above problem?
b. What kind of probability distribution does the above satisfy, and is there a function for solving such problems?
c. What is the probability that both customers received damaged VCRs?
d. What is the probability that one of the two customers received a defective VCR?

Accepted Answer

a. No, in a binomial experimen

Question 10

An experiment consists of determining the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is a

Accepted Answer

A)  discrete random variable 
B)  continuous random variable 
C)  complex random variable 
D)  simplex random variable 
A)  discrete random variable 
B)  continuous random variable 
C)  complex random variable 
D)  simplex random variable

Question 11

The variance is a measure of dispersion or variability of a random variable. It is a weighted average of the

Accepted Answer

A)  square root of the deviations from the mean 
B)  square root of the deviations from the median 
C)  squared deviations from the median 
D)  squared deviations from the mean 
A)  square root of the deviations from the mean 
B)  square root of the deviations from the median 
C)  squared deviations from the median 
D)  squared deviations from the mean

Question 12

Exhibit 5-11
A local bottling company has determined the number of machine breakdowns per month and their respective probabilities as shown below:
 $\begin{array}{ll}\text { Number of } & \
\text { Breakdowns  } & \text { Prabability } \
0 & 0.12 \
1 & 0.38 \
2 & 0.25 \
3 & 0.18 \
4 & 0.07
\end{array}$
-Refer to Exhibit 5-11. The probability of no breakdowns in a month is

Accepted Answer

A)  0.88 
B)  0.00 
C)  0.50 
D)  0.12 
A)  0.88 
B)  0.00 
C)  0.50 
D)  0.12

Question 13

A local university reports that 10% of their students take their general education courses on a pass/fail basis. Assume that fifteen students are registered for a general education course.
a. What is the expected number of students who have registered on a pass/fail basis?
b. What is the probability that exactly five are registered on a pass/fail basis?
c. What is the probability that more than four are registered on a pass/fail basis?
d. What is the probability that less than two are registered on a pass/fail basis?

Accepted Answer

a. 1.5
b.

Question 14

Exhibit 5-3
Roth 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.
 $$\begin{array} { c c } 
\text { Number of } & \
\text { New Clients } & \text { Prabability } \
0 & 0.05 \
1 & 0.10 \
2 & 0.15 \
3 & 0.35 \
4 & 0.20 \
5 & 0.10 \
6 & 0.05
\end{array}$$
-Refer to Exhibit 5-3. The expected number of new clients per month is

Accepted Answer

A)  6 
B)  0 
C)  3.05 
D)  21 
A)  6 
B)  0 
C)  3.05 
D)  21

Question 15

The student body of a large university consists of 30% Business majors. A random sample of 20 students is selected.
a. What is the probability that among the students in the sample at least 10 are Business majors?
b. What is the probability that at least 16 are not Business majors?
c. What is the probability that exactly 10 are Business majors?
d. What is the probability that exactly 12 are not Business majors?

Accepted Answer

a. 0.0479

Question 16

Exhibit 5-6
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.
 $\begin{array}{ll}\text { Cups of Coffee }&\text { Frequency }\
0 & 700 \
1 & 900 \
2 & 600 \
3 & 300\&2,500
\end{array}$
-Refer to Exhibit 5-6. The expected number of cups of coffee is

Accepted Answer

A)  1 
B)  1.2 
C)  1.5 
D)  1.7 
A)  1 
B)  1.2 
C)  1.5 
D)  1.7

Question 17

The weight of an object is an example of

Accepted Answer

A)  a continuous random variable 
B)  a discrete random variable 
C)  either a continuous or a discrete random variable, depending on the weight of the object 
D)  either a continuous or a discrete random variable depending on the units of measurement 
A)  a continuous random variable 
B)  a discrete random variable 
C)  either a continuous or a discrete random variable, depending on the weight of the object 
D)  either a continuous or a discrete random variable depending on the units of measurement

Question 18

A random variable that can assume only a finite number of values is referred to as an)

Accepted Answer

A)  infinite sequence 
B)  finite sequence 
C)  discrete random variable 
D)  discrete probability function 
A)  infinite sequence 
B)  finite sequence 
C)  discrete random variable 
D)  discrete probability function

Question 19

The records of a department store show that 20% of its customers who make a purchase return the merchandise in order to exchange it. In the next six purchases,
a. what is the probability that three customers will return the merchandise for exchange?
b. what is the probability that four customers will return the merchandise for exchange?
c. what is the probability that none of the customers will return the merchandise for exchange?

Accepted Answer

a. 0.0819

Question 20

Assume that you have a binomial experiment with p = 0.5 and a sample size of 100. The value of the standard deviation is

Accepted Answer

A)  50 
B)  2 
C)  25 
D)  5 
A)  50 
B)  2 
C)  25 
D)  5

A measure of the average value of a random variable is called an)

Exhibit 5-4 Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected. -Refer to Exhibit 5-4. The probability that there are no females in the sample is

Exhibit 5-1 The following represents the probability distribution for the daily demand of computers at a local store. Demand Probability 0 0.1 1 0.2 2 0.3 3 0.2 4 0? -Refer to Exhibit 5-1. The probability of having a demand for at least two computers is

Exhibit 5-5 Probability Distribution x fx) 10 .2 20 .3 30 .4 40 .1 -Refer to Exhibit 5-5. The variance of x equals

The standard deviation is the

A continuous random variable may assume

A description of the distribution of the values of a random variable and their associated probabilities is called a

Exhibit 5-7 The probability that Pete will catch fish when he goes fishing is .8. Pete is going to fish 3 days next week. Define the random variable X to be the number of days Pete catches fish. -Refer to Exhibit 5-7. The probability that Pete will catch fish on one day or less is

An experiment consists of determining the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is a

The variance is a measure of dispersion or variability of a random variable. It is a weighted average of the

Exhibit 5-11 A local bottling company has determined the number of machine breakdowns per month and their respective probabilities as shown below: Number of Breakdowns Prabability 0 0.12 1 0.38 2 0.25 3 0.18 4 0.07 -Refer to Exhibit 5-11. The probability of no breakdowns in a month is

Exhibit 5-6 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. Cups of Coffee Frequency 0 700 1 900 2 600 3 300 2,500 -Refer to Exhibit 5-6. The expected number of cups of coffee is

The weight of an object is an example of

A random variable that can assume only a finite number of values is referred to as an)

Assume that you have a binomial experiment with p = 0.5 and a sample size of 100. The value of 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

Comparisons Involving Means, Experimental Design, and Analysis of Variance

Comparisons Involving Proportions and a Test of Independence

Simple Linear Regression

Multiple Regression

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Exam 5: Discrete Probability Distributions

A measure of the average value of a random variable is called an)

Exhibit 5-4 Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected. -Refer to Exhibit 5-4. The probability that there are no females in the sample is

Exhibit 5-1 The following represents the probability distribution for the daily demand of computers at a local store. Demand Probability 0 0.1 1 0.2 2 0.3 3 0.2 4 0? -Refer to Exhibit 5-1. The probability of having a demand for at least two computers is

Exhibit 5-5 Probability Distribution x fx) 10 .2 20 .3 30 .4 40 .1 -Refer to Exhibit 5-5. The variance of x equals

The standard deviation is the

A continuous random variable may assume

A description of the distribution of the values of a random variable and their associated probabilities is called a

Exhibit 5-7 The probability that Pete will catch fish when he goes fishing is .8. Pete is going to fish 3 days next week. Define the random variable X to be the number of days Pete catches fish. -Refer to Exhibit 5-7. The probability that Pete will catch fish on one day or less is

An experiment consists of determining the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is a

The variance is a measure of dispersion or variability of a random variable. It is a weighted average of the

Exhibit 5-11 A local bottling company has determined the number of machine breakdowns per month and their respective probabilities as shown below: Number of Breakdowns Prabability 0 0.12 1 0.38 2 0.25 3 0.18 4 0.07 -Refer to Exhibit 5-11. The probability of no breakdowns in a month is

Exhibit 5-6 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. Cups of Coffee Frequency 0 700 1 900 2 600 3 300 2,500 -Refer to Exhibit 5-6. The expected number of cups of coffee is

The weight of an object is an example of

A random variable that can assume only a finite number of values is referred to as an)

Assume that you have a binomial experiment with p = 0.5 and a sample size of 100. The value of 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

Comparisons Involving Means, Experimental Design, and Analysis of Variance

Comparisons Involving Proportions and a Test of Independence

Simple Linear Regression

Multiple Regression

Filters