Question 1

The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored 90 or higher?

Accepted Answer

A)  0.4979 
B)  0.0021 
C)  0.9979 
D)  2.86

Question 2

To apply the normal approximation to a binomial distribution what must be true? ________________

Accepted Answer

The answer of To apply the normal approximation to a...

Question 3

What is the area under the normal curve between z = -1.0 and z = -2.0?

Accepted Answer

A)  0.0228 
B)  0.3413 
C)  0.1359 
D)  0.4772

Question 4

Suppose a tire manufacturer wants to set a mileage guarantee on its new XB 70 tire. Tests revealed that the tire's mileage is normally distributed with a mean of 47,900 miles and a standard deviation of 2,050 miles. The manufacturer wants to set the guaranteed mileage so that no more than 5 percent of the tires will have to be replaced. What guaranteed mileage should the manufacturer announce?

Accepted Answer

A)  44,528 
B)  32,960 
C)  49,621 
D)  40,922

Question 5

A major credit card company has determined that customers charge between $100 and $1100 per month. Given that the average monthly amount charged is uniformly distributed, what percent of monthly changes are between $311 and $889? ________

Accepted Answer

The answer of A major credit card company has determined...

Question 6

A study conducted by a local tennis center revealed that 25 percent of its new members have novice level tennis skills. A membership drive in a metropolitan area resulted in 500 new members. What is the mean and standard deviation to apply the normal approximation to the binomial?

Accepted Answer

The answer of A study conducted by a local tennis...

Question 7

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs between 20.75 and 23.25 ounces? _____

Accepted Answer

The answer of The weight of a bag of corn...

Question 8

If an average of 12 customers is served per hour, what is the probability that the next customer will arrive in 6 minutes or less?

Accepted Answer

A)  0.61 
B)  0.30 
C)  0.70 
D)  0.39

Question 9

The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what test score separates the top 5% of the students from the lower 95% of students?

Accepted Answer

A)  81.48 
B)  90.00 
C)  83.72 
D)  78.96

Question 10

A large manufacturing firm tests job applicants who recently graduated from college. The test scores are normally distributed with a mean of 500 and a standard deviation of 50. Management is considering placing a new hire in an upper level management position if the person scores in the upper 6 percent of the distribution. What is the lowest score a college graduate must earn to qualify for a responsible position?

Accepted Answer

A)  50 
B)  625 
C)  460 
D)  578

Question 11

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs more than 23 ounces? _____

Accepted Answer

The answer of The weight of a bag of corn...

Question 12

The exponential distribution can be used to predict ________.

Accepted Answer

The answer of The exponential distribution can be used to...

Question 13

The mean of a normal probability distribution is 500 and the standard deviation is 10. About 95 percent of the observations lie between what two values?

Accepted Answer

A)  475 and 525 
B)  480 and 520 
C)  400 and 600 
D)  350 and 650

Question 14

Non-stop Airlines determined that the mean number of passengers per flight is 152 with a standard deviation of ten passengers. Practically all flights have between 142 and 162 passengers.

Accepted Answer

A) True 
 B)False

Question 15

The normal distribution can be used to approximate a binomial distribution when n$\pi$ is less than 5.

Accepted Answer

A) True 
 B)False

Question 16

The standard normal probability distribution is unique because it has:

Accepted Answer

A)  A mean of 1 and any standard deviation 
B)  Any mean and a standard deviation of 1 
C)  A mean of 0 and any standard deviation 
D)  A mean of 0 and a standard deviation of 1

Question 17

About what percent of the area under the normal curve is within plus two and minus two standard deviation of the mean? _______

Accepted Answer

The answer of About what percent of the area under...

Question 18

A "continuity correction factor" is used to compute probabilities when using the normal distribution to approximate the binomial distribution.

Accepted Answer

A) True 
 B)False

Question 19

What proportion of the area under a normal curve is to the right of z = -1.21? ________

Accepted Answer

The answer of What proportion of the area under a...

Question 20

A major credit card company has determined that customers charge between $100 and $1100 per month. Given that the average monthly amount charged is uniformly distributed, what percent of monthly charges are between $600 and $889? ____________

Accepted Answer

The answer of A major credit card company has determined...

Exam 7: Continuous Probability Distributions

The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored 90 or higher?

To apply the normal approximation to a binomial distribution what must be true? ________________

What is the area under the normal curve between z = -1.0 and z = -2.0?

A major credit card company has determined that customers charge between $100 and $1100 per month. Given that the average monthly amount charged is uniformly distributed, what percent of monthly changes are between $311 and $889? ________

A study conducted by a local tennis center revealed that 25 percent of its new members have novice level tennis skills. A membership drive in a metropolitan area resulted in 500 new members. What is the mean and standard deviation to apply the normal approximation to the binomial?

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs between 20.75 and 23.25 ounces? _____

If an average of 12 customers is served per hour, what is the probability that the next customer will arrive in 6 minutes or less?

The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what test score separates the top 5% of the students from the lower 95% of students?

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs more than 23 ounces? _____

The exponential distribution can be used to predict ________.

The mean of a normal probability distribution is 500 and the standard deviation is 10. About 95 percent of the observations lie between what two values?

Non-stop Airlines determined that the mean number of passengers per flight is 152 with a standard deviation of ten passengers. Practically all flights have between 142 and 162 passengers.

The normal distribution can be used to approximate a binomial distribution when n $\pi$ is less than 5.

The standard normal probability distribution is unique because it has:

About what percent of the area under the normal curve is within plus two and minus two standard deviation of the mean? _______

A "continuity correction factor" is used to compute probabilities when using the normal distribution to approximate the binomial distribution.

What proportion of the area under a normal curve is to the right of z = -1.21? ________

A major credit card company has determined that customers charge between $100 and $1100 per month. Given that the average monthly amount charged is uniformly distributed, what percent of monthly charges are between $600 and $889? ____________

Exam 7: Continuous Probability Distributions

The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what is the probability that a student scored 90 or higher?

To apply the normal approximation to a binomial distribution what must be true? ________________

What is the area under the normal curve between z = -1.0 and z = -2.0?

A major credit card company has determined that customers charge between $100 and $1100 per month. Given that the average monthly amount charged is uniformly distributed, what percent of monthly changes are between $311 and $889? ________

A study conducted by a local tennis center revealed that 25 percent of its new members have novice level tennis skills. A membership drive in a metropolitan area resulted in 500 new members. What is the mean and standard deviation to apply the normal approximation to the binomial?

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs between 20.75 and 23.25 ounces? _____

If an average of 12 customers is served per hour, what is the probability that the next customer will arrive in 6 minutes or less?

The average score of 100 students taking a statistics final was 70 with a standard deviation of 7. Assuming a normal distribution, what test score separates the top 5% of the students from the lower 95% of students?

The weight of a bag of corn chips is normally distributed with a mean of 22 ounces and a standard deviation of ½ ounces. What is the probability that a bag of corn chips weighs more than 23 ounces? _____

The exponential distribution can be used to predict ________.

The mean of a normal probability distribution is 500 and the standard deviation is 10. About 95 percent of the observations lie between what two values?

Non-stop Airlines determined that the mean number of passengers per flight is 152 with a standard deviation of ten passengers. Practically all flights have between 142 and 162 passengers.

The normal distribution can be used to approximate a binomial distribution when n π\piπ is less than 5.

The standard normal probability distribution is unique because it has:

About what percent of the area under the normal curve is within plus two and minus two standard deviation of the mean? _______

A "continuity correction factor" is used to compute probabilities when using the normal distribution to approximate the binomial distribution.

What proportion of the area under a normal curve is to the right of z = -1.21? ________

A major credit card company has determined that customers charge between $100 and $1100 per month. Given that the average monthly amount charged is uniformly distributed, what percent of monthly charges are between $600 and $889? ____________

The normal distribution can be used to approximate a binomial distribution when n $\pi$ is less than 5.