Question 1

Given that Z is a standard normal random variable,what is the value of Z if the area to the right of Z is 0.5?

Accepted Answer

A) 0.0000 
B) 1.0000 
C) 0.1915 
D) 0.3413

Question 2

The function that defines the probability distribution of a continuous random variable is a

Accepted Answer

A) normal function 
B) uniform function 
C) either normal of uniform depending on the situation 
D) probability density function

Question 3

The z score for the standard normal distribution

Accepted Answer

A) is always equal to zero 
B) can never be negative 
C) can be either negative or positive 
D) is always equal to the mean

Question 4

Given that Z is a standard normal random variable,what is the probability that -2.08  Z  1.46?

Accepted Answer

A) 0.9091 
B) 0.4812 
C) 0.4279 
D) 0.0533

Question 5

Given that Z is a standard normal random variable,what is the value of Z if the area between -Z and Z is 0.901?

Accepted Answer

A) 1.96 
B) -1.96 
C) 0.4505 
D) 1.65

Question 6

The time required to assemble a part of a machine follows an exponential probability distribution with a mean of 14 minutes.
a.What is the probability that the part can be assembled in 7 minutes or less?
b.What is the probability that the part can be assembled between 3.5 and 7 minutes?

Accepted Answer

The answer of The time required to assemble a part...

Question 7

Exhibit 6-2
The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds.
-Refer to Exhibit 6-2.The probability of a player weighing more than 241.25 pounds is

Accepted Answer

A) 0.4505 
B) 0.0495 
C) 0.9505 
D) 0.9010

Question 8

The life expectancy of computer terminals is normally distributed with a mean of 4 years and a standard deviation of 10 months.
a.What is the probability that a randomly selected terminal will last more than 5 years?
b.What percentage of terminals will last between 5 and 6 years?
c.What percentage of terminals will last less than 4 years?
d.What percentage of terminals will last between 2.5 and 4.5 years?
e.If the manufacturer guarantees the terminals for 3 years (and will replace them if they malfunction),what percentage of terminals will be replaced?

Accepted Answer

The answer of The life expectancy of computer terminals is...

Question 9

A local bank has determined that the daily balances of the checking accounts of its customers are normally distributed with an average of $280 and a standard deviation of $20.
a.What percentage of its customers has daily balances of more than $275?
b.What percentage of its customers has daily balances less than $243?
c.What percentage of its customers' balances is between $241 and $301.60?

Accepted Answer

The answer of A local bank has determined that the...

Question 10

Exhibit 6-7
The weight of items produced by a machine is normally distributed with a mean of 8 ounces and a standard deviation of 2 ounces.
-Refer to Exhibit 6-7.What percentage of items will weigh at least 11.7 ounces?

Accepted Answer

A) 46.78% 
B) 96.78% 
C) 3.22% 
D) 53.22%

Question 11

Exhibit 6-6
The starting salaries of individuals with an MBA degree are normally distributed with a mean of $40,000 and a standard deviation of $5,000.
-Refer to Exhibit 6-6.What is the probability that a randomly selected individual with an MBA degree will get a starting salary of at least $47,500?

Accepted Answer

A) 0.4332 
B) 0.9332 
C) 0.0668 
D) 0.5000

Question 12

Exhibit 6-5
The travel time for a college student traveling between her home and her college is uniformly distributed between 40 and 90 minutes.
-Refer to Exhibit 6-5.The probability that her trip will take longer than 60 minutes is

Accepted Answer

A) 1.00 
B) 0.40 
C) 0.02 
D) 0.600

Question 13

The time it takes a mechanic to change the oil in a car is exponentially distributed with a mean of 5 minutes.
a.What is the probability density function for the time it takes to change the oil?
b.What is the probability that it will take a mechanic less than 6 minutes to change the oil?
c.What is the probability that it will take a mechanic between 3 and 5 minutes to change the oil?
d.What is the variance of the time it takes to change the oil?

Accepted Answer

The answer of The time it takes a mechanic to...

Question 14

The Mathematics part of the SAT scores of students at UTC are normally distributed with a mean of 500 and a standard deviation of 75.
a.If 2.28 percent of the students who had the highest scores received scholarships,what was the minimum score among those who received scholarships? Do not round your answer.
b.It is known that 6.3 percent of students who applied to UTC were not accepted.What is the highest score of those who were denied acceptance? Do not round your answer.
c.What percentage of students had scores between 575 and 650?

Accepted Answer

The answer of The Mathematics part of the SAT scores...

Question 15

Which of the following is not a characteristic of the normal probability distribution?

Accepted Answer

A) The mean,median,and the mode are equal 
B) The mean of the distribution can be negative,zero,or positive 
C) The distribution is symmetrical 
D) The standard deviation must be 1

Question 16

The ticket sales for events held at the new civic center are believed to be normally distributed with a mean of 12,000 and a standard deviation of 1,000.
a.What is the probability of selling more than 10,000 tickets?
b.What is the probability of selling between 9,500 and 11,000 tickets?
c.What is the probability of selling more than 13,500 tickets?

Accepted Answer

The answer of The ticket sales for events held at...

Question 17

The probability that a continuous random variable takes any specific value

Accepted Answer

A) is equal to zero 
B) is at least 0.5 
C) depends on the probability density function 
D) is very close to 1.0

Question 18

When a continuous probability distribution is used to approximate a discrete probability distribution

Accepted Answer

A) a value of 0.5 is added and/or subtracted from the area 
B) a value of 0.5 is added and/or subtracted from the value of x 
C) a value of 0.5 is added to the area 
D) a value of 0.5 is subtracted from the area

Question 19

Z is a standard normal random variable.The P(1.05 < Z < 2.13)equals

Accepted Answer

A) 0.8365 
B) 0.1303 
C) 0.4834 
D) 0.3531

Question 20

The First National Mortgage Company has noted that 6% of its customers pay their mortgage payments after the due date.
a.What is the probability that in a random sample of 150 customers 7 will be late on their payments?
b.What is the probability that in a random sample of 150 customers at least 10 will be late on their payments?

Accepted Answer

The answer of The First National Mortgage Company has noted...

Exam 6: Continuous Probability Distributions

Given that Z is a standard normal random variable,what is the value of Z if the area to the right of Z is 0.5?

The function that defines the probability distribution of a continuous random variable is a

The z score for the standard normal distribution

Given that Z is a standard normal random variable,what is the probability that -2.08 Z 1.46?

Given that Z is a standard normal random variable,what is the value of Z if the area between -Z and Z is 0.901?

The time required to assemble a part of a machine follows an exponential probability distribution with a mean of 14 minutes. a.What is the probability that the part can be assembled in 7 minutes or less? b.What is the probability that the part can be assembled between 3.5 and 7 minutes?

Exhibit 6-2 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. -Refer to Exhibit 6-2.The probability of a player weighing more than 241.25 pounds is

Exhibit 6-7 The weight of items produced by a machine is normally distributed with a mean of 8 ounces and a standard deviation of 2 ounces. -Refer to Exhibit 6-7.What percentage of items will weigh at least 11.7 ounces?

Exhibit 6-6 The starting salaries of individuals with an MBA degree are normally distributed with a mean of $40,000 and a standard deviation of $5,000. -Refer to Exhibit 6-6.What is the probability that a randomly selected individual with an MBA degree will get a starting salary of at least $47,500?

Exhibit 6-5 The travel time for a college student traveling between her home and her college is uniformly distributed between 40 and 90 minutes. -Refer to Exhibit 6-5.The probability that her trip will take longer than 60 minutes is

Which of the following is not a characteristic of the normal probability distribution?

The probability that a continuous random variable takes any specific value

When a continuous probability distribution is used to approximate a discrete probability distribution

Z is a standard normal random variable.The P(1.05 < Z < 2.13) equals