Question 1

If the mileage per gallon for a car is normally distributed,32 mpg has a z score of 1.2,and 24 mpg has a z score of -.4,what is the mean mpg of the distribution?

Accepted Answer

A) 28 
B) 26 
C) 30 
D) 38 
A) 28 
B) 26 
C) 30 
D) 38

Question 2

A plant manager knows that the number of boxes of supplies received weekly is normally distributed with a mean of 200 and a standard deviation of 20.What percentage of the time will the number of boxes received weekly be fewer than 160?

Accepted Answer

A) 2.28% 
B) 57.93% 
C) 42.07% 
D) 4.56% 
A) 2.28% 
B) 57.93% 
C) 42.07% 
D) 4.56%

Question 3

The number of defective pencils in a lot of 1000 is an example of a continuous random variable.

Accepted Answer

A) True 
 B)False

Question 4

For a continuous distribution,P(X ≤ 100)= P(X < 100).

Accepted Answer

A) True 
 B)False

Question 5

While conducting experiments,a marine biologist selects water depths from a uniformly distributed collection that vary between 2.00 m and 7.00 m.What is the standard deviation of the water depth?

Accepted Answer

A) 1.4 
B) 2.6 
C) 2.5 
D) 4.5 
A) 1.4 
B) 2.6 
C) 2.5 
D) 4.5

Question 6

The binomial random variable x consists of n = 60 trials and has the probability of failure q = 0.4.Using the normal approximation,compute the probability of 19 successes.

Accepted Answer

The answer of The binomial random variable x consists of...

Question 7

_____________ values of the standard deviation result in a normal curve that is narrower and more peaked.

Accepted Answer

A) Smaller 
B) Equal 
C) Larger 
D) Uniform 
A) Smaller 
B) Equal 
C) Larger 
D) Uniform

Question 8

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.Find the probability that a household spent more than $16.00 on sugar.

Accepted Answer

A) 1.00 
B) 0.00 
C) 0.50 
D) 0.98 
A) 1.00 
B) 0.00 
C) 0.50 
D) 0.98

Question 9

Given that the length an athlete throws a hammer is a normal random variable with mean 50 feet and standard deviation 5 feet,what is the probability he throws it no less than 55 feet?

Accepted Answer

A) .8413 
B) .1587 
C) .6826 
D) .3174 
A) .8413 
B) .1587 
C) .6826 
D) .3174

Question 10

A uniform distribution f(x)is a continuous probability distribution,which says the probability that x is in any 2 intervals of equal length is the same.

Accepted Answer

A) True 
 B)False

Question 11

For a continuous distribution,the exact probability of a particular value is zero.

Accepted Answer

A) True 
 B)False

Question 12

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.Find the probability that a household spent less than $5.00 on sugar.

Accepted Answer

A) .9983 
B) 0.000 
C) 1.00 
D) 0.0017 
A) .9983 
B) 0.000 
C) 1.00 
D) 0.0017

Question 13

Suppose that the waiting time for a license plate renewal at a local office of a state motor vehicle department has been found to be normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes.Complete the following statement: Only 20 percent of the individuals wait less than _____ minutes.

Accepted Answer

A) 36.72 
B) 23.28 
C) 34.63 
D) 25.37 
A) 36.72 
B) 23.28 
C) 34.63 
D) 25.37

Question 14

Consider a normal population with a mean of 10 and a variance of 4.Find P(X > 7).

Accepted Answer

A) .0668 
B) .9332 
C) .8413 
D) .1587 
A) .0668 
B) .9332 
C) .8413 
D) .1587

Question 15

The standardized normal quartile value Oi is the z value that gives an area of i/(n - 1)to its right under the normal curve.

Accepted Answer

A) True 
 B)False

Question 16

In order to approximate the binomial distribution using the normal distribution,the following condition(s)must be met if p is near 1.

Accepted Answer

A) np > 5 only 
B) n must be larger than just meeting the condition of np > 5 
C) n can be as small as np > 5 
D) n > 5 
A) np > 5 only 
B) n must be larger than just meeting the condition of np > 5 
C) n can be as small as np > 5 
D) n > 5

Question 17

The ___________ is a graphic that is used to check visually whether data come from a normal population.

Accepted Answer

A) Exponential plot 
B) Normal probability plot 
C) Box and whiskers plot 
D) Normal distribution graph 
A) Exponential plot 
B) Normal probability plot 
C) Box and whiskers plot 
D) Normal distribution graph

Question 18

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.80 percent of the households spent more than what amount?

Accepted Answer

A) $7.30 
B) $7.38 
C) $9.06 
D) $9.14 
A) $7.30 
B) $7.38 
C) $9.06 
D) $9.14

Question 19

The random variable x has a uniform distribution when x lies between the values of 4 and 10.When x = 10,what is the value of f(x)?

Accepted Answer

A) 0 
B) 1 
C) 1/6 
D) 1/14 
A) 0 
B) 1 
C) 1/6 
D) 1/14

Question 20

Suppose the distribution of personal daily water usage in New York City is normally distributed with a mean of 15 gallons and a variance of 25 gallons.Because of a current problem with the distribution of water to its citizens,the mayor wants to give a city tax rebate to the 15 percent of the population who use the least amount of water.What should he use as the water limit for a person to qualify for a city tax rebate?

Accepted Answer

A) 9.825 
B) 15.00 
C) 12.20 
D) 10.25 
A) 9.825 
B) 15.00 
C) 12.20 
D) 10.25

If the mileage per gallon for a car is normally distributed,32 mpg has a z score of 1.2,and 24 mpg has a z score of -.4,what is the mean mpg of the distribution?

A plant manager knows that the number of boxes of supplies received weekly is normally distributed with a mean of 200 and a standard deviation of 20.What percentage of the time will the number of boxes received weekly be fewer than 160?

The number of defective pencils in a lot of 1000 is an example of a continuous random variable.

For a continuous distribution,P(X ≤ 100)= P(X < 100).

While conducting experiments,a marine biologist selects water depths from a uniformly distributed collection that vary between 2.00 m and 7.00 m.What is the standard deviation of the water depth?

The binomial random variable x consists of n = 60 trials and has the probability of failure q = 0.4.Using the normal approximation,compute the probability of 19 successes.

_____________ values of the standard deviation result in a normal curve that is narrower and more peaked.

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.Find the probability that a household spent more than $16.00 on sugar.

Given that the length an athlete throws a hammer is a normal random variable with mean 50 feet and standard deviation 5 feet,what is the probability he throws it no less than 55 feet?

A uniform distribution f(x)is a continuous probability distribution,which says the probability that x is in any 2 intervals of equal length is the same.

For a continuous distribution,the exact probability of a particular value is zero.

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.Find the probability that a household spent less than $5.00 on sugar.

Consider a normal population with a mean of 10 and a variance of 4.Find P(X > 7).

The standardized normal quartile value O_i is the z value that gives an area of i/(n - 1)to its right under the normal curve.

In order to approximate the binomial distribution using the normal distribution,the following condition(s)must be met if p is near 1.

The ___________ is a graphic that is used to check visually whether data come from a normal population.

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.80 percent of the households spent more than what amount?

The random variable x has a uniform distribution when x lies between the values of 4 and 10.When x = 10,what is the value of f(x)?

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Sampling and Sampling Distributions

Confidence Intervals

Hypothesis Testing

Statistical Inferences Based on Two Samples

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Process Improvement Using Control Charts

Filters

Exam 6: Continuous Random Variables

If the mileage per gallon for a car is normally distributed,32 mpg has a z score of 1.2,and 24 mpg has a z score of -.4,what is the mean mpg of the distribution?

A plant manager knows that the number of boxes of supplies received weekly is normally distributed with a mean of 200 and a standard deviation of 20.What percentage of the time will the number of boxes received weekly be fewer than 160?

The number of defective pencils in a lot of 1000 is an example of a continuous random variable.

For a continuous distribution,P(X ≤ 100)= P(X < 100).

While conducting experiments,a marine biologist selects water depths from a uniformly distributed collection that vary between 2.00 m and 7.00 m.What is the standard deviation of the water depth?

The binomial random variable x consists of n = 60 trials and has the probability of failure q = 0.4.Using the normal approximation,compute the probability of 19 successes.

_____________ values of the standard deviation result in a normal curve that is narrower and more peaked.

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.Find the probability that a household spent more than $16.00 on sugar.

Given that the length an athlete throws a hammer is a normal random variable with mean 50 feet and standard deviation 5 feet,what is the probability he throws it no less than 55 feet?

A uniform distribution f(x)is a continuous probability distribution,which says the probability that x is in any 2 intervals of equal length is the same.

For a continuous distribution,the exact probability of a particular value is zero.

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.Find the probability that a household spent less than $5.00 on sugar.

Consider a normal population with a mean of 10 and a variance of 4.Find P(X > 7).

The standardized normal quartile value Oi is the z value that gives an area of i/(n - 1)to its right under the normal curve.

In order to approximate the binomial distribution using the normal distribution,the following condition(s)must be met if p is near 1.

The ___________ is a graphic that is used to check visually whether data come from a normal population.

During the past six months,73.2 percent of US households purchased sugar.Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10.80 percent of the households spent more than what amount?

The random variable x has a uniform distribution when x lies between the values of 4 and 10.When x = 10,what is the value of f(x)?

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Sampling and Sampling Distributions

Confidence Intervals

Hypothesis Testing

Statistical Inferences Based on Two Samples

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Process Improvement Using Control Charts

Filters

The standardized normal quartile value O_i is the z value that gives an area of i/(n - 1)to its right under the normal curve.