Question 1

The normal distribution is a very good approximation to the binomial distribution whenever ____________________ and ____________________ are ≥ 5.

Accepted Answer

The answer of The normal distribution is a very good...

Question 2

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 more than $95?

Accepted Answer

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

Question 3

A very large logging operation has serious problems keeping their skidders operating properly.The equipment fails at the rate of 3 breakdowns every 48 hours.Assume that x is time between breakdowns and is exponentially distributed.The probability of two or less breakdowns in the next 48-hour period is:

Accepted Answer

A)  0.9672. 
B)  0.0307. 
C)  0.2231. 
D)  0.7769. 
A)  0.9672. 
B)  0.0307. 
C)  0.2231. 
D)  0.7769.

Question 4

Use the properties of the standard normal curve to describe the method of finding the area to the right of z = 1.42.

Accepted Answer

Since the standard normal table in text

Question 5

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 ≤ 9).

Accepted Answer

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

Question 6

A dispatcher for an airport shuttle averages sending a van to the airport 2 times every 60 minutes.The distribution is Poisson,and the driver must take a 15-minute lunch break.The probability that he can finish lunch before getting a call is:

Accepted Answer

A)  0.1350. 
B)  0.6065. 
C)  0.3935. 
D)  1.6490. 
E)  0.8650. 
A)  0.1350. 
B)  0.6065. 
C)  0.3935. 
D)  1.6490. 
E)  0.8650.

Question 7

A bakery firm finds that its average weight of the most popular package of cookies is 32.06 ounces with a standard deviation of 0.1 ounces.What portion of cookie packages will weigh less than 31.9 ounces or more than 32.3 ounces?

Accepted Answer

A)  0.8000 
B)  0.4452 
C)  0.4918 
D)  0.9370 
E)  0.0630 
A)  0.8000 
B)  0.4452 
C)  0.4918 
D)  0.9370 
E)  0.0630

Question 8

The age of customers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years.What is the probability that the next customer who enters the store will be more than 31 years old?

Accepted Answer

The answer of The age of customers for a particular...

Question 9

The age of customers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years.What is the probability that the next customer who enters the store will be between 40 and 45 years old?

Accepted Answer

The answer of The age of customers for a particular...

Question 10

A salesman who uses his car extensively finds that his gasoline bills average $125.32 per month with a standard deviation of $49.51.The probability that his bill will be less than $50 a month or more than $150 for a single month is:

Accepted Answer

A)  0.4357. 
B)  0.1915. 
C)  0.6272. 
D)  0.3728. 
E)  0.6915. 
A)  0.4357. 
B)  0.1915. 
C)  0.6272. 
D)  0.3728. 
E)  0.6915.

Question 11

The average labor time to sew a pair of denim jeans is 4.2 hours with a standard deviation of 30 minutes.If the distribution is normal,then the probability of a worker finishing a pair of jeans in less than 3.5 hours is:

Accepted Answer

A)  0.0808. 
B)  0.4192. 
C)  0.5808. 
D)  0.9192. 
E)  0.9808. 
A)  0.0808. 
B)  0.4192. 
C)  0.5808. 
D)  0.9192. 
E)  0.9808.

Question 12

Given that z is a standard normal random variable and that the area to the right of z is 0.1949,then the value of z must be:

Accepted Answer

A)  0.51. 
B)  -0.51. 
C)  0.86. 
D)  -0.86. 
A)  0.51. 
B)  -0.51. 
C)  0.86. 
D)  -0.86.

Question 13

In any normal distribution,the mean,median,mode,and standard deviation are all at the same position on the horizontal axis.

Accepted Answer

A) True 
 B)False

Question 14

Scores of high school students on a national mathematics exam in Egypt were normally distributed with a mean of 86 and a standard deviation of 4.
A)What is the probability that a randomly selected student will have a score of 80 or higher?
B)If there were 97,680 students with scores higher than 91,how many students took the test?
____________________ (Remove all commas from your answer before submitting).

Accepted Answer

The answer of Scores of high school students on a...

Question 15

The average waiting time at the checkout counter for a large grocery chain is 2.45 minutes with a standard deviation of 24 seconds (0.40 minutes).Assume that the distribution of waiting time is normal.What is the probability that a customer must wait more than 3 minutes for check out?

Accepted Answer

The answer of The average waiting time at the checkout...

Question 16

Identify the distribution shown in the following graph.Indicate the approximate areas that will lie beneath the curve for the intervals shown.

Accepted Answer

The answer of Identify the distribution shown in the following...

Question 17

If the area to the right of a positive z1 is 0.0869,then the value of z1 must be:

Accepted Answer

A)  -1.36. 
B)  1.36. 
C)  1.71. 
D)  1.80. 
E)  0.22. 
A)  -1.36. 
B)  1.36. 
C)  1.71. 
D)  1.80. 
E)  0.22.

Question 18

Women make up 58% of the U.S.civilian workforce of 124 million.The U.S.Department of Commerce randomly selects 100 workers for a conference on national health care.What is the probability that more than 20 of these workers are female?

Accepted Answer

0.9999 or

Question 19

Using the standard normal table,the total area between z = 0.45 and z = 1.05 is:

Accepted Answer

A)  0.1736 
B)  0.3531 
C)  0.3264 
D)  0.6469 
E)  0.1795 
A)  0.1736 
B)  0.3531 
C)  0.3264 
D)  0.6469 
E)  0.1795

Question 20

Computer statistical packages,such as Excel and Minitab,can determine the exact area beneath a specified portion of the continuous distribution curve,or probability density function,and eliminate the need for calculations or table references.

Accepted Answer

A) True 
 B)False

The normal distribution is a very good approximation to the binomial distribution whenever and are ≥ 5.

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 more than $95?

Use the properties of the standard normal curve to describe the method of finding the area to the right of z = 1.42.

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 ≤ 9).

A dispatcher for an airport shuttle averages sending a van to the airport 2 times every 60 minutes.The distribution is Poisson,and the driver must take a 15-minute lunch break.The probability that he can finish lunch before getting a call is:

A bakery firm finds that its average weight of the most popular package of cookies is 32.06 ounces with a standard deviation of 0.1 ounces.What portion of cookie packages will weigh less than 31.9 ounces or more than 32.3 ounces?

The age of customers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years.What is the probability that the next customer who enters the store will be more than 31 years old?

The age of customers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years.What is the probability that the next customer who enters the store will be between 40 and 45 years old?

A salesman who uses his car extensively finds that his gasoline bills average $125.32 per month with a standard deviation of $49.51.The probability that his bill will be less than $50 a month or more than $150 for a single month is:

The average labor time to sew a pair of denim jeans is 4.2 hours with a standard deviation of 30 minutes.If the distribution is normal,then the probability of a worker finishing a pair of jeans in less than 3.5 hours is:

Given that z is a standard normal random variable and that the area to the right of z is 0.1949,then the value of z must be:

In any normal distribution,the mean,median,mode,and standard deviation are all at the same position on the horizontal axis.

The average waiting time at the checkout counter for a large grocery chain is 2.45 minutes with a standard deviation of 24 seconds (0.40 minutes).Assume that the distribution of waiting time is normal.What is the probability that a customer must wait more than 3 minutes for check out?

Identify the distribution shown in the following graph.Indicate the approximate areas that will lie beneath the curve for the intervals shown.

If the area to the right of a positive z₁ is 0.0869,then the value of z₁ must be:

Women make up 58% of the U.S.civilian workforce of 124 million.The U.S.Department of Commerce randomly selects 100 workers for a conference on national health care.What is the probability that more than 20 of these workers are female?

Using the standard normal table,the total area between z = 0.45 and z = 1.05 is:

Computer statistical packages,such as Excel and Minitab,can determine the exact area beneath a specified portion of the continuous distribution curve,or probability density function,and eliminate the need for calculations or table references.

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 normal distribution is a very good approximation to the binomial distribution whenever ____________________ and ____________________ are ≥ 5.

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 more than $95?

Use the properties of the standard normal curve to describe the method of finding the area to the right of z = 1.42.

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 ≤ 9).

A dispatcher for an airport shuttle averages sending a van to the airport 2 times every 60 minutes.The distribution is Poisson,and the driver must take a 15-minute lunch break.The probability that he can finish lunch before getting a call is:

A bakery firm finds that its average weight of the most popular package of cookies is 32.06 ounces with a standard deviation of 0.1 ounces.What portion of cookie packages will weigh less than 31.9 ounces or more than 32.3 ounces?

The age of customers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years.What is the probability that the next customer who enters the store will be more than 31 years old?

The age of customers for a particular retail store follows a normal distribution with a mean of 37.5 years and a standard deviation of 7.6 years.What is the probability that the next customer who enters the store will be between 40 and 45 years old?

A salesman who uses his car extensively finds that his gasoline bills average $125.32 per month with a standard deviation of $49.51.The probability that his bill will be less than $50 a month or more than $150 for a single month is:

The average labor time to sew a pair of denim jeans is 4.2 hours with a standard deviation of 30 minutes.If the distribution is normal,then the probability of a worker finishing a pair of jeans in less than 3.5 hours is:

Given that z is a standard normal random variable and that the area to the right of z is 0.1949,then the value of z must be:

In any normal distribution,the mean,median,mode,and standard deviation are all at the same position on the horizontal axis.

The average waiting time at the checkout counter for a large grocery chain is 2.45 minutes with a standard deviation of 24 seconds (0.40 minutes).Assume that the distribution of waiting time is normal.What is the probability that a customer must wait more than 3 minutes for check out?

Identify the distribution shown in the following graph.Indicate the approximate areas that will lie beneath the curve for the intervals shown.

If the area to the right of a positive z1 is 0.0869,then the value of z1 must be:

Women make up 58% of the U.S.civilian workforce of 124 million.The U.S.Department of Commerce randomly selects 100 workers for a conference on national health care.What is the probability that more than 20 of these workers are female?

Using the standard normal table,the total area between z = 0.45 and z = 1.05 is:

Computer statistical packages,such as Excel and Minitab,can determine the exact area beneath a specified portion of the continuous distribution curve,or probability density function,and eliminate the need for calculations or table references.

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

The normal distribution is a very good approximation to the binomial distribution whenever and are ≥ 5.

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 ≤ 9).

If the area to the right of a positive z₁ is 0.0869,then the value of z₁ must be: