Question 1

The standard normal distribution has a mean of 0.0 and standard deviation of 1.0.

Accepted Answer

A) True 
 B)False

Question 2

Find z1 if the area to the left of a positive z1 is 0.9131.

Accepted Answer

Question 3

If the mean of an exponential distribution is 2,then the value of the parameter $\lambda$ is:

Accepted Answer

A)  4.0. 
B)  2.2. 
C)  1.0. 
D)  0.5. 
A)  4.0. 
B)  2.2. 
C)  1.0. 
D)  0.5.

Question 4

Given that z is a standard normal random variable,a negative value of z indicates that:

Accepted Answer

A)  The value z is to the left of the mean. 
B)  The value z is to the right of the median. 
C)  The standard deviation of z is negative. 
D)  The area between zero and z is negative. 
E)  The probability associated with z is negative. 
A)  The value z is to the left of the mean. 
B)  The value z is to the right of the median. 
C)  The standard deviation of z is negative. 
D)  The area between zero and z is negative. 
E)  The probability associated with z is negative.

Question 5

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes.What is the probability that it will take a technician less than 10 minutes to fix a computer problem?

Accepted Answer

The answer of The time it takes a technician to...

Question 6

Assume x is normally distributed with mean $\mu$ = 15 and standard deviation $\text { σ }$ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(x = 20).

Accepted Answer

The answer of Assume x is normally distributed with mean...

Question 7

The selling price of various homes in a community follows the normal distribution with a mean of $176,000 and a standard deviation of $22,300.What is the probability that the next house will sell for between $150,000 and $168,000?

Accepted Answer

The answer of The selling price of various homes in...

Question 8

Complete the following table indicating which procedure to use in calculating binomial probabilities:
 $$\begin{array} { | c | c | c | } 
\hline n & \pi & \text { Procedure } \
\hline \text { Large } & 0 .2 \leq \pi \leq 0 . 8 & \
\hline \text { Large } & 0 .0 \leq \pi \leq 0.1 & \
\hline \text { Large } & 0.9 \leq \pi \leq 1.0 & \
\hline \text { Small } & 0 .0 \leq \pi \leq 1.0 & \
\hline
\end{array}$$

Accepted Answer

\[\begin{array} { | c | c | c | } 
\hlin

Question 9

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes.What is the probability density function for the time it takes a technician to fix a computer problem?

Accepted Answer

f(x)= (1/1

Question 10

In 2000,the average charge of tax preparation was $95.Assuming a normal distribution and a standard deviation of $10,use the approximate areas beneath the normal curve,as discussed in this section,to answer: What proportion of tax preparation fees were between $80 and $90?

Accepted Answer

The answer of In 2000,the average charge of tax preparation...

Question 11

In 2000,the average charge of tax preparation was $95.Assuming a normal distribution and a standard deviation of $10,use the approximate areas beneath the normal curve,as discussed in this section,to answer: What proportion of tax preparation fees were between $75 and $115?

Accepted Answer

The answer of In 2000,the average charge of tax preparation...

Question 12

Which of the following statements are true regarding the normal distribution curve?

Accepted Answer

A)  It is symmetrical. 
B)  It is bell-shaped. 
C)  It is asymptotic in that each end approaches the horizontal axis,but never reaches it. 
D)  Its mean,median,and mode are located at the same position. 
E)  All of these statements are true. 
A)  It is symmetrical. 
B)  It is bell-shaped. 
C)  It is asymptotic in that each end approaches the horizontal axis,but never reaches it. 
D)  Its mean,median,and mode are located at the same position. 
E)  All of these statements are true.

Question 13

For the standard normal curve,determine the area to the right of z = 0.34.

Accepted Answer

The answer of For the standard normal curve,determine the area...

Question 14

Assume x is normally distributed with mean $\mu$ = 15 and standard deviation $\text { σ }$ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(9 ≤ x ≤ 21).

Accepted Answer

The answer of Assume x is normally distributed with mean...

Question 15

If the z-value for a given value x of the random variable x is z = 1.96,and the distribution of x is normally distributed with a mean of 60 and a standard deviation of 6,then the x-value that this z-value corresponds to is:

Accepted Answer

A)  71.76. 
B)  67.96. 
C)  61.96. 
D)  48.24. 
A)  71.76. 
B)  67.96. 
C)  61.96. 
D)  48.24.

Question 16

In 1997,private planes had 1.5 fatal crashes per 100 thousand flying hours.Assume a continuous random variable with a exponential distribution.A national association of private plane owners has 560 members who fly 1.5 million miles each year.The mileage crash rate has been estimated to be 20 per 100 million miles of air travel.What is the probability that the next crash by a member of the association will not occur until more than one year from now?

Accepted Answer

The answer of In 1997,private planes had 1.5 fatal crashes...

Question 17

Like the normal distribution,the exponential density function f(x):

Accepted Answer

A)  is bell-shaped. 
B)  is symmetrical. 
C)  approaches infinity as x approaches zero. 
D)  approaches zero as x approaches infinity. 
A)  is bell-shaped. 
B)  is symmetrical. 
C)  approaches infinity as x approaches zero. 
D)  approaches zero as x approaches infinity.

Question 18

An efficiency expert makes periodic checks for weighting errors for a long distance shipping firm.The expert inspects for errors in weighing,in recording weights,and errors in processing the bills of lading.Based on past records,the number of weekly errors for all shipments averages 5.30 with a standard deviation of 1.23,and the frequency histogram approximates a normal distribution.Suppose x is the number of weighing errors that will occur next week.
Compute the approximate probability for (4 ≤ x ≤ 7).

Accepted Answer

The answer of An efficiency expert makes periodic checks for...

Question 19

The z-score representing the 75th percentile of the standard normal distribution is:

Accepted Answer

A)  0.67. 
B)  -0.67. 
C)  1.28. 
D)  -1.28. 
E)  1.645. 
A)  0.67. 
B)  -0.67. 
C)  1.28. 
D)  -1.28. 
E)  1.645.

Question 20

For a normal curve,if the mean is 20 minutes and the standard deviation is 5 minutes,then the area between 11 and 19 minutes is:

Accepted Answer

A)  0.4641. 
B)  0.0359. 
C)  0.3848. 
D)  0.8848. 
E)  0.9641. 
A)  0.4641. 
B)  0.0359. 
C)  0.3848. 
D)  0.8848. 
E)  0.9641.

The standard normal distribution has a mean of 0.0 and standard deviation of 1.0.

Find z₁ if the area to the left of a positive z₁ is 0.9131.

If the mean of an exponential distribution is 2,then the value of the parameter $\lambda$ is:

Given that z is a standard normal random variable,a negative value of z indicates that:

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes.What is the probability that it will take a technician less than 10 minutes to fix a computer problem?

Assume x is normally distributed with mean $\mu$ = 15 and standard deviation $\text { σ }$ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(x = 20).

The selling price of various homes in a community follows the normal distribution with a mean of $176,000 and a standard deviation of $22,300.What is the probability that the next house will sell for between $150,000 and $168,000?

Complete the following table indicating which procedure to use in calculating binomial probabilities: n \pi Procedure Large 0.2\leq\pi\leq0.8 Large 0.0\leq\pi\leq0.1 Large 0.9\leq\pi\leq1.0 Small 0.0\leq\pi\leq1.0

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes.What is the probability density function for the time it takes a technician to fix a computer problem?

In 2000,the average charge of tax preparation was $95.Assuming a normal distribution and a standard deviation of $10,use the approximate areas beneath the normal curve,as discussed in this section,to answer: What proportion of tax preparation fees were between $80 and $90?

In 2000,the average charge of tax preparation was $95.Assuming a normal distribution and a standard deviation of $10,use the approximate areas beneath the normal curve,as discussed in this section,to answer: What proportion of tax preparation fees were between $75 and $115?

Which of the following statements are true regarding the normal distribution curve?

For the standard normal curve,determine the area to the right of z = 0.34.

Assume x is normally distributed with mean $\mu$ = 15 and standard deviation $\text { σ }$ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(9 ≤ x ≤ 21).

If the z-value for a given value x of the random variable x is z = 1.96,and the distribution of x is normally distributed with a mean of 60 and a standard deviation of 6,then the x-value that this z-value corresponds to is:

Like the normal distribution,the exponential density function f(x):

The z-score representing the 75th percentile of the standard normal distribution is:

For a normal curve,if the mean is 20 minutes and the standard deviation is 5 minutes,then the area between 11 and 19 minutes is:

A Preview of Business Statistics

Visual Description of Data

Statistical Description of Data

Data Collection and Sampling Methods

Probability: Review of Basic Concepts

Discrete Probability Distributions

Sampling Distributions

Estimation From Sample Data

Hypothesis Tests Involving a Sample Mean or Proportion

Hypothesis Tests Involving Two Sample Means

Analysis of Variance Tests

Chi-Square Applications

Nonparametric Methods

Simple Linear Regression and Correlation

Multiple Regression and Correlation

Model Building

Models for Time Series and Forecasting

Decision Theory

Total Quality Management

Filters

Exam 7: Continuous Probability Distributions

The standard normal distribution has a mean of 0.0 and standard deviation of 1.0.

Find z1 if the area to the left of a positive z1 is 0.9131.

If the mean of an exponential distribution is 2,then the value of the parameter λ\lambdaλ is:

Given that z is a standard normal random variable,a negative value of z indicates that:

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes.What is the probability that it will take a technician less than 10 minutes to fix a computer problem?

Assume x is normally distributed with mean μ\muμ = 15 and standard deviation σ \text { σ } σ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(x = 20).

The selling price of various homes in a community follows the normal distribution with a mean of $176,000 and a standard deviation of $22,300.What is the probability that the next house will sell for between $150,000 and $168,000?

Complete the following table indicating which procedure to use in calculating binomial probabilities: n \pi Procedure Large 0.2\leq\pi\leq0.8 Large 0.0\leq\pi\leq0.1 Large 0.9\leq\pi\leq1.0 Small 0.0\leq\pi\leq1.0

The time it takes a technician to fix a computer problem is exponentially distributed with a mean of 15 minutes.What is the probability density function for the time it takes a technician to fix a computer problem?

In 2000,the average charge of tax preparation was $95.Assuming a normal distribution and a standard deviation of $10,use the approximate areas beneath the normal curve,as discussed in this section,to answer: What proportion of tax preparation fees were between $80 and $90?

In 2000,the average charge of tax preparation was $95.Assuming a normal distribution and a standard deviation of $10,use the approximate areas beneath the normal curve,as discussed in this section,to answer: What proportion of tax preparation fees were between $75 and $115?

Which of the following statements are true regarding the normal distribution curve?

For the standard normal curve,determine the area to the right of z = 0.34.

Assume x is normally distributed with mean μ\muμ = 15 and standard deviation σ \text { σ } σ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(9 ≤ x ≤ 21).

If the z-value for a given value x of the random variable x is z = 1.96,and the distribution of x is normally distributed with a mean of 60 and a standard deviation of 6,then the x-value that this z-value corresponds to is:

Like the normal distribution,the exponential density function f(x):

The z-score representing the 75th percentile of the standard normal distribution is:

For a normal curve,if the mean is 20 minutes and the standard deviation is 5 minutes,then the area between 11 and 19 minutes is:

A Preview of Business Statistics

Visual Description of Data

Statistical Description of Data

Data Collection and Sampling Methods

Probability: Review of Basic Concepts

Discrete Probability Distributions

Sampling Distributions

Estimation From Sample Data

Hypothesis Tests Involving a Sample Mean or Proportion

Hypothesis Tests Involving Two Sample Means

Analysis of Variance Tests

Chi-Square Applications

Nonparametric Methods

Simple Linear Regression and Correlation

Multiple Regression and Correlation

Model Building

Models for Time Series and Forecasting

Decision Theory

Total Quality Management

Filters

Find z₁ if the area to the left of a positive z₁ is 0.9131.

If the mean of an exponential distribution is 2,then the value of the parameter $\lambda$ is:

Assume x is normally distributed with mean $\mu$ = 15 and standard deviation $\text { σ }$ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(x = 20).

Assume x is normally distributed with mean $\mu$ = 15 and standard deviation $\text { σ }$ = 3.Use the approximate areas beneath the normal curve,as discussed in this section,to find P(9 ≤ x ≤ 21).