Question 1

Excel's NORM.S.DIST function can be used to compute

Accepted Answer

A) cumulative probabilities for a standard normal z value 
B) the standard normal z value given a cumulative probability 
C) cumulative probabilities for a normally distributed x value 
D) the normally distributed x value given a cumulative probability

Question 2

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 3

Exhibit 6-4
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 6-4. 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 4

Exhibit 6-3
The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds.
-Refer to Exhibit 6-3. The probability of a player weighing less than 250 pounds is

Accepted Answer

A) 0.4772 
B) 0.9772 
C) 0.0528 
D) 0.5000

Question 5

A continuous probability distribution that is useful in describing the time, or space, between occurrences of an event is a(n)

Accepted Answer

A) normal probability distribution 
B) uniform probability distribution 
C) exponential probability distribution 
D) Poisson probability distribution

Question 6

If arrivals follow a Poisson probability distribution, the time between successive arrivals must follow

Accepted Answer

A) a Poisson probability distribution 
B) a normal probability distribution 
C) a uniform probability distribution 
D) an exponential probability distribution

Question 7

Exhibit 6-6
The life expectancy of a particular brand of tire is normally distributed with a mean of 40,000 and a standard deviation of 5,000 miles.
-Refer to Exhibit 6-6. What is the probability that a randomly selected tire will have a life of exactly 47,500 miles?

Accepted Answer

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

Question 8

Exhibit 6-3
The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds.
-Refer to Exhibit 6-3. What is the random variable in this experiment?

Accepted Answer

A) the weight of football players 
B) 200 pounds 
C) 25 pounds 
D) the normal distribution

Question 9

The time it takes to completely tune an engine of an automobile follows an exponential distribution with a mean of 40 minutes.
a.Define the random variable in words.
b.What is the probability of tuning an engine in 30 minutes or less?
c.What is the probability of tuning an engine between 30 and 35 minutes?

Accepted Answer

The answer of The time it takes to completely tune...

Question 10

The assembly time for a product is uniformly distributed between 6 to 10 minutes. The expected assembly time (in minutes) is

Accepted Answer

A) 16 
B) 2 
C) 8 
D) 4

Question 11

Exhibit 6-2
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 6-2. What is the random variable in this experiment?

Accepted Answer

A) the uniform distribution 
B) 40 minutes 
C) 90 minutes 
D) the travel time

Question 12

Exhibit 6-7 
-A random variable x is uniformly distributed between 45 and 150.
a.Determine the probability of x = 48.
b.What is the probability of x $\le$ 60?
c.What is the probability of x $\ge$ 50?
d.Determine the expected vale of x and its standard deviation.

Accepted Answer

The answer of Exhibit 6-7 
-A random variable x is...

Question 13

Exhibit 6-4
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 6-4. What percentage of MBA's will have starting salaries of $34,000 to $46,000?

Accepted Answer

A) 38.49% 
B) 38.59% 
C) 50% 
D) 76.98%

Question 14

The average starting salary for this year's graduates of a large community college is $30,000 with a standard deviation of $8,000. Furthermore, it is known that the starting salaries are normally distributed.
a.What is the probability that a randomly selected graduate of this community college will have a starting salary of at least $30,400?
b.Individuals with starting salaries of less than $15,600 receive a low income tax break. What percentage of the graduates will receive the tax break?
c.What are the minimum and the maximum starting salaries of the middle 95% of the graduates?
d.If 303 of the recent graduates have salaries of at least $43,120, how many students graduated this year from this community college?

Accepted Answer

The answer of The average starting salary for this year's...

Question 15

Delicious Candy markets a two-pound box of assorted chocolates. Because of imperfections in the candy making equipment, the actual weight of the chocolate has a uniform distribution ranging from 31.8 to 32.6 ounces.
a. Define a probability density function for the weight of the box of chocolate.
b. What is the probability that a box weighs (1) exactly 32 ounces; (2) more than 32.3 ounces; (3) less than 31.8 ounces?
c. The government requires that at least 60% of all products sold weigh at least as much as the stated weight. Is Delicious violating government regulations?

Accepted Answer

The answer of Delicious Candy markets a two-pound box of...

Question 16

X is a normally distributed random variable with a mean of 50 and a standard deviation of 5. Use Excel to calculate the following:
a.P(x $\le$ 45)
b.P(45 $\le$ x $\le$ 55)
c.P(x $\ge$ 55)
d.x value with .20 in the lower tail
e.x value with .01 in the upper tail

Accepted Answer

The answer of X is a normally distributed random variable...

Question 17

Z is a standard normal random variable. What is the value of z if the area to the right of z is 0.9803?

Accepted Answer

A) -2.06 
B) 0.4803 
C) 0.0997 
D) 3.06

Question 18

For a standard normal distribution, the probability of z $\le$ 0 is

Accepted Answer

A) zero 
B) -0.5 
C) 0.5 
D) one

Question 19

Exhibit 6-5
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 6-5. What is the probability that a randomly selected item will weigh more than 10 ounces?

Accepted Answer

A) 0.3413 
B) 0.8413 
C) 0.1587 
D) 0.5000

Question 20

For any continuous random variable, the probability that the random variable takes on exactly a specific value is

Accepted Answer

A) 1.00 
B) 0.50 
C) any value between 0 to 1 
D) zero

Exam 6: Continuous Probability Distributions

Excel's NORM.S.DIST function can be used to compute

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 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. -Refer to Exhibit 6-3. The probability of a player weighing less than 250 pounds is

A continuous probability distribution that is useful in describing the time, or space, between occurrences of an event is a(n)

If arrivals follow a Poisson probability distribution, the time between successive arrivals must follow

Exhibit 6-6 The life expectancy of a particular brand of tire is normally distributed with a mean of 40,000 and a standard deviation of 5,000 miles. -Refer to Exhibit 6-6. What is the probability that a randomly selected tire will have a life of exactly 47,500 miles?

Exhibit 6-3 The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. -Refer to Exhibit 6-3. What is the random variable in this experiment?

The assembly time for a product is uniformly distributed between 6 to 10 minutes. The expected assembly time (in minutes) is

Exhibit 6-2 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 6-2. What is the random variable in this experiment?

Exhibit 6-7 -A random variable x is uniformly distributed between 45 and 150. a.Determine the probability of x = 48. b.What is the probability of x ≤\le≤ 60? c.What is the probability of x ≥\ge≥ 50? d.Determine the expected vale of x and its standard deviation.

Exhibit 6-4 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 6-4. What percentage of MBA's will have starting salaries of $34,000 to $46,000?

X is a normally distributed random variable with a mean of 50 and a standard deviation of 5. Use Excel to calculate the following: a.P(x ≤\le≤ 45) b.P(45 ≤\le≤ x ≤\le≤ 55) c.P(x ≥\ge≥ 55) d.x value with .20 in the lower tail e.x value with .01 in the upper tail

Z is a standard normal random variable. What is the value of z if the area to the right of z is 0.9803?

For a standard normal distribution, the probability of z ≤\le≤ 0 is

Exhibit 6-5 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 6-5. What is the probability that a randomly selected item will weigh more than 10 ounces?

For any continuous random variable, the probability that the random variable takes on exactly a specific value is

X is a normally distributed random variable with a mean of 50 and a standard deviation of 5. Use Excel to calculate the following: a.P(x $\le$ 45) b.P(45 $\le$ x $\le$ 55) c.P(x $\ge$ 55) d.x value with .20 in the lower tail e.x value with .01 in the upper tail

For a standard normal distribution, the probability of z $\le$ 0 is