Question 1

A continuous random variable x is normally distributed with a mean of $250 and a standard deviation of $50.Find the z-score for x = 285.

Accepted Answer

The answer of A continuous random variable x is normally...

Question 2

Which of the following distributions is suitable to model the length of time that elapses before the first telephone call is received by a switchboard?

Accepted Answer

A)  Exponential 
B)  Normal 
C)  Poisson 
D)  Binomial 
E)  Hypergeometric 
A)  Exponential 
B)  Normal 
C)  Poisson 
D)  Binomial 
E)  Hypergeometric

Question 3

The recent average starting salary for new college graduates in computer information systems is $47,500.Assume salaries are normally distributed with a standard deviation of $4,500.What is the probability of a new graduate receiving a salary between $45,000 and $50,000?

Accepted Answer

The answer of The recent average starting salary for new...

Question 4

For a normal curve,if the mean is 20 minutes and the standard deviation is 5 minutes,then the area between 22 and 25 minutes is:

Accepted Answer

A)  0.3413. 
B)  0.1554. 
C)  0.4967. 
D)  0.1859. 
E)  0.2248. 
A)  0.3413. 
B)  0.1554. 
C)  0.4967. 
D)  0.1859. 
E)  0.2248.

Question 5

If we ____________________ the normal curve,we express the original x values in terms of their number of standard deviations away from the mean.

Accepted Answer

The answer of If we ____________________ the normal curve,we express...

Question 6

The mean of the exponential distribution equals the mean of the Poisson distribution only when the former distribution has a mean equals:

Accepted Answer

A)  1.00. 
B)  0.50. 
C)  0.25. 
D)  2.00. 
A)  1.00. 
B)  0.50. 
C)  0.25. 
D)  2.00.

Question 7

A continuous probability distribution represents a random variable:

Accepted Answer

A)  having outcomes,which occur in counting numbers. 
B)  having an infinite number of outcomes which may assume any number of values within an interval. 
C)  which is best described in a histogram. 
D)  which has a definite probability for the occurrence of a given integer. 
E)  None of these is correct. 
A)  having outcomes,which occur in counting numbers. 
B)  having an infinite number of outcomes which may assume any number of values within an interval. 
C)  which is best described in a histogram. 
D)  which has a definite probability for the occurrence of a given integer. 
E)  None of these is correct.

Question 8

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 ≥
 15).

Accepted Answer

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

Question 9

A continuous random variable x is normally distributed with a mean of 120 grams and a standard deviation of 30 grams.Convert x = 106 into its corresponding z-score.

Accepted Answer

The answer of A continuous random variable x is normally...

Question 10

A circus performer who gets shot from a cannon is supposed to land in a safety net positioned at the other end of the arena.The distance he travels is normally distributed with a mean of 175 feet and a standard deviation of 15 feet.His landing net is 50 feet long and the mid-point of the net is positioned 175 feet from the cannon.What is the probability that the performer will miss the net on a given night?

Accepted Answer

The answer of A circus performer who gets shot from...

Question 11

A continuous random variable x has the following probability density function:
f(x)= 2e-2x ,x ≥ 0
What is the distribution of the random variable x?

Accepted Answer

Exponentia

Question 12

Which of the following is not a correct statement?

Accepted Answer

A)  The exponential distribution describes the Poisson process as a continuous random variable. 
B)  The exponential distribution is a family of curves,which are completely described by the mean. 
C)  The mean of the exponential distribution is the complement of the mean of the Poisson. 
D)  The Poisson is a probability distribution or a discrete random variable while the exponential distribution is continuous. 
E)  All of these are correct. 
A)  The exponential distribution describes the Poisson process as a continuous random variable. 
B)  The exponential distribution is a family of curves,which are completely described by the mean. 
C)  The mean of the exponential distribution is the complement of the mean of the Poisson. 
D)  The Poisson is a probability distribution or a discrete random variable while the exponential distribution is continuous. 
E)  All of these are correct.

Question 13

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 proportion of the customers are served in between 1 minute and 2.5 minutes?

Accepted Answer

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

Question 14

Using the standard normal table,the total area between z = -0.75 and z = 1.21 is:

Accepted Answer

A)  0.2734 
B)  0.3869 
C)  0.3397 
D)  0.2266 
E)  0.6603 
A)  0.2734 
B)  0.3869 
C)  0.3397 
D)  0.2266 
E)  0.6603

Question 15

Determine P(-2.45 ≤ z ≤ 0),assuming a standard normal distribution.

Accepted Answer

The answer of Determine P(-2.45 ≤ z ≤ 0),assuming a...

Question 16

Although the binomial distribution is discrete and the normal distribution is continuous,the normal distribution is a good approximation to the binomial whenever both ____________________ and ____________________ are ≥ 5,where n = number of trials,and $\pi$ = the probability of success in any given trial,are the parameters of the binomial distribution.

Accepted Answer

The answer of Although the binomial distribution is discrete and...

Question 17

Any normal distribution is a symmetrical,bell-shaped curve,with mean $\mu$ = 0.0 and standard deviation $\text { ? }$ = 1.0.

Accepted Answer

A) True 
 B)False

Question 18

Find the z-score that determines that the area to the left of z is 0.9292.

Accepted Answer

The answer of Find the z-score that determines that the...

Question 19

The probability that any continuous random variable x will take on any specific value along an interval is ____________________.

Accepted Answer

The answer of The probability that any continuous random variable...

Question 20

An elementary school teacher learned that 40 percent of school age children have at least 3 cavities.The teacher has 30 students in his class.What is the probability that 10 students from this class have at least 3 cavities?

Accepted Answer

The answer of An elementary school teacher learned that 40...

A continuous random variable x is normally distributed with a mean of $250 and a standard deviation of $50.Find the z-score for x = 285.

Which of the following distributions is suitable to model the length of time that elapses before the first telephone call is received by a switchboard?

The recent average starting salary for new college graduates in computer information systems is $47,500.Assume salaries are normally distributed with a standard deviation of $4,500.What is the probability of a new graduate receiving a salary between $45,000 and $50,000?

For a normal curve,if the mean is 20 minutes and the standard deviation is 5 minutes,then the area between 22 and 25 minutes is:

If we ____________________ the normal curve,we express the original x values in terms of their number of standard deviations away from the mean.

The mean of the exponential distribution equals the mean of the Poisson distribution only when the former distribution has a mean equals:

A continuous probability distribution represents a random variable:

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 ≥ 15).

A continuous random variable x is normally distributed with a mean of 120 grams and a standard deviation of 30 grams.Convert x = 106 into its corresponding z-score.

A continuous random variable x has the following probability density function: f(x)= 2e^-2^x,x ≥ 0 What is the distribution of the random variable x?

Which of the following is not a correct statement?

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 proportion of the customers are served in between 1 minute and 2.5 minutes?

Using the standard normal table,the total area between z = -0.75 and z = 1.21 is:

Determine P(-2.45 ≤ z ≤ 0),assuming a standard normal distribution.

Any normal distribution is a symmetrical,bell-shaped curve,with mean $\mu$ = 0.0 and standard deviation $\text { ? }$ = 1.0.

Find the z-score that determines that the area to the left of z is 0.9292.

The probability that any continuous random variable x will take on any specific value along an interval is ____________________.

An elementary school teacher learned that 40 percent of school age children have at least 3 cavities.The teacher has 30 students in his class.What is the probability that 10 students from this class have at least 3 cavities?

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

A continuous random variable x is normally distributed with a mean of $250 and a standard deviation of $50.Find the z-score for x = 285.

Which of the following distributions is suitable to model the length of time that elapses before the first telephone call is received by a switchboard?

The recent average starting salary for new college graduates in computer information systems is $47,500.Assume salaries are normally distributed with a standard deviation of $4,500.What is the probability of a new graduate receiving a salary between $45,000 and $50,000?

For a normal curve,if the mean is 20 minutes and the standard deviation is 5 minutes,then the area between 22 and 25 minutes is:

If we ____________________ the normal curve,we express the original x values in terms of their number of standard deviations away from the mean.

The mean of the exponential distribution equals the mean of the Poisson distribution only when the former distribution has a mean equals:

A continuous probability distribution represents a random variable:

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 ≥ 15).

A continuous random variable x is normally distributed with a mean of 120 grams and a standard deviation of 30 grams.Convert x = 106 into its corresponding z-score.

A continuous random variable x has the following probability density function: f(x)= 2e-2x ,x ≥ 0 What is the distribution of the random variable x?

Which of the following is not a correct statement?

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 proportion of the customers are served in between 1 minute and 2.5 minutes?

Using the standard normal table,the total area between z = -0.75 and z = 1.21 is:

Determine P(-2.45 ≤ z ≤ 0),assuming a standard normal distribution.

Any normal distribution is a symmetrical,bell-shaped curve,with mean μ\muμ = 0.0 and standard deviation ? \text { ? } ? = 1.0.

Find the z-score that determines that the area to the left of z is 0.9292.

The probability that any continuous random variable x will take on any specific value along an interval is ____________________.

An elementary school teacher learned that 40 percent of school age children have at least 3 cavities.The teacher has 30 students in his class.What is the probability that 10 students from this class have at least 3 cavities?

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

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 ≥ 15).

A continuous random variable x has the following probability density function: f(x)= 2e^-2^x,x ≥ 0 What is the distribution of the random variable x?

Any normal distribution is a symmetrical,bell-shaped curve,with mean $\mu$ = 0.0 and standard deviation $\text { ? }$ = 1.0.