Question 1

Which of the following probability distributions could be used to describe the distribution for a continuous random variable?

Accepted Answer

A)  Exponential distribution 
B)  Normal distribution 
C)  Uniform distribution 
D)  All of the above 
A)  Exponential distribution 
B)  Normal distribution 
C)  Uniform distribution 
D)  All of the above

Question 2

The manager at a local movie theater has collected data for a long period of time and has concluded that the revenue from concession sales during the first show each evening is normally distributed with a mean equal to $336.25 and a standard deviation equal to $80. Based on this information, what are the chances that the revenue on the first show will be between $300 and $500?

Accepted Answer

A)  About 0.3062 
B)  Approximately 0.6534 
C)  0.1736 
D)  Approximately 0.4798 
A)  About 0.3062 
B)  Approximately 0.6534 
C)  0.1736 
D)  Approximately 0.4798

Question 3

For a standardized normal distribution, determine a value, say z0, so that P(-z0 ≤ z < 0) = 0.45.

Accepted Answer

A)  1.84 
B)  1.645 
C)  1.96 
D)  1.33 
A)  1.84 
B)  1.645 
C)  1.96 
D)  1.33

Question 4

The manager of a computer help desk operation has collected enough data to conclude that the distribution of time per call is normally distributed with a mean equal to 8.21 minutes and a standard deviation of 2.14 minutes. Based on this, what is the probability that a call will last longer than 13 minutes?

Accepted Answer

A)  About 0.0125 
B)  Approximately 0.4875 
C)  About 0.5125 
D)  About 0.9875 
A)  About 0.0125 
B)  Approximately 0.4875 
C)  About 0.5125 
D)  About 0.9875

Question 5

The actual weight of 2-pound sacks of salted peanuts is found to be normally distributed with a mean equal to 2.04 pounds and a standard deviation of 0.25 pounds. Given this information, the probability of a sack weighing more than 2.40 pounds is 0.4251.

Accepted Answer

A) True 
 B)False

Question 6

For the normal distribution with parameters μ = 4, σ = 3; calculate P(x > 1).

Accepted Answer

A)  0.8413 
B)  0.4562 
C)  0.7812 
D)  0.4152 
A)  0.8413 
B)  0.4562 
C)  0.7812 
D)  0.4152

Question 7

For a continuous distribution the total area under the curve is equal to 100.

Accepted Answer

A) True 
 B)False

Question 8

A continuous random variable approaches normality as the level of skewness increases.

Accepted Answer

A) True 
 B)False

Question 9

For the normal distribution with parameters μ = 0, σ = 3; calculate P(x > 1).

Accepted Answer

A)  0.5812 
B)  0.1214 
C)  0.3707 
D)  0.4412 
A)  0.5812 
B)  0.1214 
C)  0.3707 
D)  0.4412

Question 10

For a standardized normal distribution, calculate P(-1.00 < z < 1.00).

Accepted Answer

A)  0.6826 
B)  0.6667 
C)  0.4572 
D)  0.5521 
A)  0.6826 
B)  0.6667 
C)  0.4572 
D)  0.5521

Question 11

A random variable, x, has a normal distribution with μ = 13.6 and σ = 2.90. Determine a value, x0, so that P(x ≤ x0) = 0.975.

Accepted Answer

A)  16.678 
B)  19.284 
C)  23.360 
D)  14.475 
A)  16.678 
B)  19.284 
C)  23.360 
D)  14.475

Question 12

A major cell phone service provider has determined that the number of minutes that its customers use their phone per month is normally distributed with a mean equal to 445.5 minutes with a standard deviation equal to 177.8 minutes. The company is thinking of changing its fee structure so that anyone who uses the phone less than 250 minutes during a given month will pay a reduced monthly fee. Based on the available information, what percentage of current customers would be eligible for the reduced fee?

Accepted Answer

A)  About 36.4 percent 
B)  Approximately 52 percent 
C)  About 86.6 percent 
D)  About 13.6 percent 
A)  About 36.4 percent 
B)  Approximately 52 percent 
C)  About 86.6 percent 
D)  About 13.6 percent

Question 13

Students who have completed a speed reading course have reading speeds that are normally distributed with a mean of 950 words per minute and a standard deviation equal to 220 words per minute. If two students were selected at random, what is the probability that they would both read at less than 400 words per minute?

Accepted Answer

A)  0.4938 
B)  0.0062 
C)  0.00004 
D)  0.2438 
A)  0.4938 
B)  0.0062 
C)  0.00004 
D)  0.2438

Question 14

Which of the following probability distributions would most likely be used to describe the time between failures for electronic components?

Accepted Answer

A)  Binomial distribution 
B)  Exponential distribution 
C)  Uniform distribution 
D)  Normal distribution 
A)  Binomial distribution 
B)  Exponential distribution 
C)  Uniform distribution 
D)  Normal distribution

Question 15

A random variable, x, has a normal distribution with μ = 13.6 and σ = 2.90. Determine a value, x0, so that P(x > x0) = 0.05.

Accepted Answer

A)  14.46 
B)  15.33 
C)  18.37 
D)  12.45 
A)  14.46 
B)  15.33 
C)  18.37 
D)  12.45

Question 16

Consider a random variable, z, that has a standardized normal distribution. Determine P(z > -1).

Accepted Answer

A)  0.8413 
B)  0.1251 
C)  0.1512 
D)  0.2124 
A)  0.8413 
B)  0.1251 
C)  0.1512 
D)  0.2124

Question 17

The normal distribution is one of the most frequently used discrete probability distributions.

Accepted Answer

A) True 
 B)False

Question 18

For a standardized normal distribution, determine a value, say z0, so that P(-z0 ≤ z ≤ z0) = 0.95.

Accepted Answer

A)  2.14 
B)  1.65 
C)  1.96 
D)  1.24 
A)  2.14 
B)  1.65 
C)  1.96 
D)  1.24

Question 19

The State Department of Forests has determined that annual tree growth in a particular forest area is normally distributed with a mean equal to 17 inches and a standard deviation equal to 6 inches. If 2 trees are randomly chosen, the probability that both trees will have grown more than 20 inches during the year is approximately .037.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following probability distributions can be used to describe the distribution for a continuous random variable?

Accepted Answer

A)  Normal distribution 
B)  Binomial distribution 
C)  Poisson distribution 
D)  Hypergeometric 
A)  Normal distribution 
B)  Binomial distribution 
C)  Poisson distribution 
D)  Hypergeometric

Which of the following probability distributions could be used to describe the distribution for a continuous random variable?

For a standardized normal distribution, determine a value, say z0, so that P(-z0 ≤ z < 0) = 0.45.

The actual weight of 2-pound sacks of salted peanuts is found to be normally distributed with a mean equal to 2.04 pounds and a standard deviation of 0.25 pounds. Given this information, the probability of a sack weighing more than 2.40 pounds is 0.4251.

For the normal distribution with parameters μ = 4, σ = 3; calculate P(x > 1).

For a continuous distribution the total area under the curve is equal to 100.

A continuous random variable approaches normality as the level of skewness increases.

For the normal distribution with parameters μ = 0, σ = 3; calculate P(x > 1).

For a standardized normal distribution, calculate P(-1.00 < z < 1.00).

A random variable, x, has a normal distribution with μ = 13.6 and σ = 2.90. Determine a value, x0, so that P(x ≤ x0) = 0.975.

Which of the following probability distributions would most likely be used to describe the time between failures for electronic components?

A random variable, x, has a normal distribution with μ = 13.6 and σ = 2.90. Determine a value, x0, so that P(x > x0) = 0.05.

Consider a random variable, z, that has a standardized normal distribution. Determine P(z > -1).

The normal distribution is one of the most frequently used discrete probability distributions.

For a standardized normal distribution, determine a value, say z0, so that P(-z0 ≤ z ≤ z0) = 0.95.

Which of the following probability distributions can be used to describe the distribution for a continuous random variable?

The Where, Why, and How of Data Collection

Graphs, Charts and Tablesdescribing Your Data

Describing Data Using Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Introduction to Linear Regression and Correlation Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Introducing Business Analytics

Introduction to Decision Analysis

Introduction to Quality and Statistical Process Control

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Exam 6: Introduction to Continuous Probability Distributions

Which of the following probability distributions could be used to describe the distribution for a continuous random variable?

For a standardized normal distribution, determine a value, say z0, so that P(-z0 ≤ z < 0) = 0.45.

The actual weight of 2-pound sacks of salted peanuts is found to be normally distributed with a mean equal to 2.04 pounds and a standard deviation of 0.25 pounds. Given this information, the probability of a sack weighing more than 2.40 pounds is 0.4251.

For the normal distribution with parameters μ = 4, σ = 3; calculate P(x > 1).

For a continuous distribution the total area under the curve is equal to 100.

A continuous random variable approaches normality as the level of skewness increases.

For the normal distribution with parameters μ = 0, σ = 3; calculate P(x > 1).

For a standardized normal distribution, calculate P(-1.00 < z < 1.00).

A random variable, x, has a normal distribution with μ = 13.6 and σ = 2.90. Determine a value, x0, so that P(x ≤ x0) = 0.975.

Which of the following probability distributions would most likely be used to describe the time between failures for electronic components?

A random variable, x, has a normal distribution with μ = 13.6 and σ = 2.90. Determine a value, x0, so that P(x > x0) = 0.05.

Consider a random variable, z, that has a standardized normal distribution. Determine P(z > -1).

The normal distribution is one of the most frequently used discrete probability distributions.

For a standardized normal distribution, determine a value, say z0, so that P(-z0 ≤ z ≤ z0) = 0.95.

Which of the following probability distributions can be used to describe the distribution for a continuous random variable?

The Where, Why, and How of Data Collection

Graphs, Charts and Tablesdescribing Your Data

Describing Data Using Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Introduction to Linear Regression and Correlation Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Introducing Business Analytics

Introduction to Decision Analysis

Introduction to Quality and Statistical Process Control

Filters