Question 1

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Let the random variable Z follow a standard normal distribution.
-What is P(Z > -0.52)?

Accepted Answer

The answer of THE NEXT QUESTIONS ARE BASED ON THE...

Question 2

As manager of a pizza shop,you are responsible for placing the food orders.You currently have enough anchovies for 8 pizzas.You expect to have orders for 60 pizzas tonight.If 8% of all pizzas are ordered with anchovies,what is the probability that you run out of anchovies before the evening is over? Use the normal approximation for the binomial.

Accepted Answer

The answer of As manager of a pizza shop,you are...

Question 3

Which type of distribution would best model the waiting times of the departing flights at JFK international airport?

Accepted Answer

A) The uniform distribution 
B) The normal distribution 
C) The binomial distribution 
D) The exponential distribution

Question 4

If X is a normal random variable with mean of 1228 and a standard deviation of 120,the number of standard deviations from 1228 to 1380 is:

Accepted Answer

A) 10.233 
B) 3.1989 
C) 11.50 
D) 1.267

Question 5

The normal probability distribution is the continuous probability distribution used least often for economics and business applications.

Accepted Answer

A) True 
 B)False

Question 6

To approximate a discrete distribution that has many different outcomes useful in most applied business and economic problems,we are,in fact,using the:

Accepted Answer

A) Poisson distribution. 
B) normal distribution. 
C) Hypergeometric distribution. 
D) marginal distribution.

Question 7

Let the random variable Z follow a standard normal distribution,and let z1be a possible value of Z that is representing the 90th percentile of the standard normal distribution.Find the value of z1.

Accepted Answer

A) 0.67 
B) -1.28 
C) 1.28 
D) -0.67

Question 8

The normal distribution is useful for waiting-line or queuing problems and service-time problems.

Accepted Answer

A) True 
 B)False

Question 9

Given that X is a normally distributed random variable with a mean of 52 and a standard deviation of 2,the probability that X is between 48 and 56 is:

Accepted Answer

A) 0.0896 
B) 0.4104 
C) 0.5896 
D) 0.9544

Question 10

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
The life of a new type of light bulb is uniformly distributed between 1,200 and 1,600 hours.
-What is the probability that a randomly-selected light bulb burns out in less than 1,500 hours?

Accepted Answer

The answer of THE NEXT QUESTIONS ARE BASED ON THE...

Question 11

The area to the left of the mean in any normal distribution is equal to:

Accepted Answer

A) the median. 
B) the standard deviation. 
C) 1.0 
D) 0.5

Question 12

Although the binomial distribution is discrete and the normal distribution is continuous,the normal distribution is a good approximation for the binomial whenever nP(1 - P)> 9 where n = number of trials,and P = the probability of success in any given trial.

Accepted Answer

A) True 
 B)False

Question 13

If a data set is approximately normally distributed,then its normal probability plot will be S-shaped.

Accepted Answer

A) True 
 B)False

Question 14

When the distribution of a continuous random variable follows a uniform probability distribution and does not exceed a specific given value,its cumulative distribution function is graphed as a:

Accepted Answer

A) bell-shaped curve. 
B) polygon. 
C) rectangle. 
D) straight line.

Question 15

You are the owner of a small casino in Las Vegas.You want to reward the high-rollers who come to your casino.You want to give free accommodations to no more than 10% of your patrons.Suppose that the mean amount wagered by all patrons is $287,with a standard deviation of $15.You should give free accommodations to those individuals who wager over how much money?

Accepted Answer

The answer of You are the owner of a small...

Question 16

The time it takes to assemble an electronic component is normally distributed with a mean of 17.2 minutes and a standard deviation of 3.1 minutes.The probability is 90% that it will take at least how long to assemble a component?

Accepted Answer

The answer of The time it takes to assemble an...

Question 17

The normal curve gets closer and closer to the X-axis but never actually touches it.

Accepted Answer

A) True 
 B)False

Question 18

If the random variable x is exponentially distributed with parameter λ = 1.5,then the probability P(2 ≤ X ≤ 4)is equal to:

Accepted Answer

A) 0.6667 
B) 0.5000 
C) 0.0473 
D) 0.2500

Question 19

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Let the random variable X follow a normal distribution with a mean of 17.1 and a standard deviation of 3.2.
-What is P(X > 16)?

Accepted Answer

A) 0.3401 
B) 0.6331 
C) 0.3669 
D) 0.8326

Question 20

The total cost for a production process is equal to $1,200 plus 2.5 times the number of units produced.The mean and variance for the number of units produced are 520 and 840,respectively.Find the mean and variance of the total cost.

Accepted Answer

The answer of The total cost for a production process...

Exam 5: Continuous Random Variables and Probability Distributions

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: Let the random variable Z follow a standard normal distribution. -What is P(Z > -0.52)?

Which type of distribution would best model the waiting times of the departing flights at JFK international airport?

If X is a normal random variable with mean of 1228 and a standard deviation of 120,the number of standard deviations from 1228 to 1380 is:

The normal probability distribution is the continuous probability distribution used least often for economics and business applications.

To approximate a discrete distribution that has many different outcomes useful in most applied business and economic problems,we are,in fact,using the:

Let the random variable Z follow a standard normal distribution,and let z₁be a possible value of Z that is representing the 90th percentile of the standard normal distribution.Find the value of z_1.

The normal distribution is useful for waiting-line or queuing problems and service-time problems.

Given that X is a normally distributed random variable with a mean of 52 and a standard deviation of 2,the probability that X is between 48 and 56 is:

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: The life of a new type of light bulb is uniformly distributed between 1,200 and 1,600 hours. -What is the probability that a randomly-selected light bulb burns out in less than 1,500 hours?

The area to the left of the mean in any normal distribution is equal to:

Although the binomial distribution is discrete and the normal distribution is continuous,the normal distribution is a good approximation for the binomial whenever nP(1 - P)> 9 where n = number of trials,and P = the probability of success in any given trial.

If a data set is approximately normally distributed,then its normal probability plot will be S-shaped.

When the distribution of a continuous random variable follows a uniform probability distribution and does not exceed a specific given value,its cumulative distribution function is graphed as a:

The time it takes to assemble an electronic component is normally distributed with a mean of 17.2 minutes and a standard deviation of 3.1 minutes.The probability is 90% that it will take at least how long to assemble a component?

The normal curve gets closer and closer to the X-axis but never actually touches it.

If the random variable x is exponentially distributed with parameter λ = 1.5,then the probability P(2 ≤ X ≤ 4) is equal to:

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION: Let the random variable X follow a normal distribution with a mean of 17.1 and a standard deviation of 3.2. -What is P(X > 16) ?

The total cost for a production process is equal to $1,200 plus 2.5 times the number of units produced.The mean and variance for the number of units produced are 520 and 840,respectively.Find the mean and variance of the total cost.