Question 1

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

Accepted Answer

A)  The graph of the curve is the shape of a rectangle. 
B)  The total area under the curve is always equal to 1. 
C)  The random variable assumes a value within plus or minus three standard deviations of its mean 99.72% of the time. 
D)  The mean is equal to the median, which is also equal to the mode. 
A)  The graph of the curve is the shape of a rectangle. 
B)  The total area under the curve is always equal to 1. 
C)  The random variable assumes a value within plus or minus three standard deviations of its mean 99.72% of the time. 
D)  The mean is equal to the median, which is also equal to the mode. A

Question 2

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 
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 A

Question 3

The assembly time for a product is uniformly distributed between 6 and 10 minutes. The probability of assembling the product between 7 and 9 minutes is _____.

Accepted Answer

A)  0 
B)  .50 
C)  .20 
D)  1 
A)  0 
B)  .50 
C)  .20 
D)  1 B

Question 4

The highest point of a normal curve occurs at _____.

Accepted Answer

A)  one standard deviation to the right of the mean 
B)  two standard deviations to the right of the mean 
C)  approximately three standard deviations to the right of the mean 
D)  the mean 
A)  one standard deviation to the right of the mean 
B)  two standard deviations to the right of the mean 
C)  approximately three standard deviations to the right of the mean 
D)  the mean

Question 5

About 95.4% of the values of a normal random variable are within approximately how many standard deviations of its mean?

Accepted Answer

A)  ±1.7 
B)  ±2 
C)  ±2.5 
D)  ±3 
A)  ±1.7 
B)  ±2 
C)  ±2.5 
D)  ±3

Question 6

A normal probability distribution _____.

Accepted Answer

A)  is a continuous probability distribution 
B)  is a discrete probability distribution 
C)  can be either continuous or discrete 
D)  always has a standard deviation of 1 
A)  is a continuous probability distribution 
B)  is a discrete probability distribution 
C)  can be either continuous or discrete 
D)  always has a standard deviation of 1

Question 7

Suppose x is a normally distributed random variable with a mean of 12 and a standard deviation of 3. The probability that x equals 19.62 is _____.

Accepted Answer

A)  0 
B)  .0055 
C)  .4945 
D)  .9945 
A)  0 
B)  .0055 
C)  .4945 
D)  .9945

Question 8

Given that z is a standard normal random variable, what is the value of z if the area to the right of z is .1401?

Accepted Answer

A)  1.08 
B)  .1401 
C)  2.16 
D)  -1.08 
A)  1.08 
B)  .1401 
C)  2.16 
D)  -1.08

Question 9

The standard deviation of a standard normal distribution _____.

Accepted Answer

A)  is always equal to 0 
B)  is always equal to 1 
C)  can be any positive value 
D)  can be any value 
A)  is always equal to 0 
B)  is always equal to 1 
C)  can be any positive value 
D)  can be any value

Question 10

For a standard normal distribution, a negative value of z indicates _____.

Accepted Answer

A)  a mistake has been made in computations, because z is always positive 
B)  the area corresponding to the z is negative 
C)  the z is to the left of the mean 
D)  the z is to the right of the mean 
A)  a mistake has been made in computations, because z is always positive 
B)  the area corresponding to the z is negative 
C)  the z is to the left of the mean 
D)  the z is to the right of the mean

Question 11

For a continuous random variable x, the probability density function f(x) represents _____.

Accepted Answer

A)  the probability at a given value of x 
B)  the area under the curve at x 
C)  both the probability at a given value of x and the area under the curve at x 
D)  the height of the function at x 
A)  the probability at a given value of x 
B)  the area under the curve at x 
C)  both the probability at a given value of x and the area under the curve at x 
D)  the height of the function at x

Question 12

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

Accepted Answer

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

Question 13

Assume z is a standard normal random variable. Then P(1.05 ≤ z ≤ 2.13) equals _____.

Accepted Answer

A)  .8365 
B)  .1303 
C)  .4834 
D)  None of the answers is correct. 
A)  .8365 
B)  .1303 
C)  .4834 
D)  None of the answers is correct.

Question 14

Suppose x is a normally distributed random variable with a mean of 22 and a standard deviation of 5. The probability that x is less than 9.7 is _____.

Accepted Answer

A)  0 
B)  .4931 
C)  .0069 
D)  .9931 
A)  0 
B)  .4931 
C)  .0069 
D)  .9931

Question 15

A property of the exponential distribution is that the mean equals the _____.

Accepted Answer

A)  mode 
B)  median 
C)  variance 
D)  standard deviation 
A)  mode 
B)  median 
C)  variance 
D)  standard deviation

Question 16

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

Accepted Answer

A)  The mean, median, and 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. 
A)  The mean, median, and 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 17

Suppose 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 ≤ 45)
b.
P(45 ≤ x ≤ 55)
c.
P(x ≥ 55)
d.
x value with 0.20 in the lower tail
e.
x value with 0.01 in the upper tail
​

Accepted Answer

The answer of Suppose x is a normally distributed random...

Question 18

For a standard normal distribution, the probability of obtaining a z value of less than 1.6 is _____.

Accepted Answer

A)  .1600 
B)  .0160 
C)  .0016 
D)  .9452 
A)  .1600 
B)  .0160 
C)  .0016 
D)  .9452

Question 19

Whenever the probability is proportional to the length of the interval in which the random variable can assume a value, the random variable follows a(n) _____ distribution.

Accepted Answer

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

Question 20

The Globe Fishery packs shrimp that weigh more than 1.91 ounces each in packages marked" large" and shrimp that weigh less than 0.47 ounce each into packages marked "small"; the remainder are packed in "medium" size packages. If a day's catch showed that 19.77% of the shrimp were large and 6.06% were small, determine the mean and standard deviation for the shrimp weights. Assume that the shrimps' weights are normally distributed.

Accepted Answer

mean = 1.4

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

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

The assembly time for a product is uniformly distributed between 6 and 10 minutes. The probability of assembling the product between 7 and 9 minutes is _____.

The highest point of a normal curve occurs at _____.

About 95.4% of the values of a normal random variable are within approximately how many standard deviations of its mean?

A normal probability distribution _____.

Suppose x is a normally distributed random variable with a mean of 12 and a standard deviation of 3. The probability that x equals 19.62 is _____.

Given that z is a standard normal random variable, what is the value of z if the area to the right of z is .1401?

The standard deviation of a standard normal distribution _____.

For a standard normal distribution, a negative value of z indicates _____.

For a continuous random variable x, the probability density function f(x) represents _____.

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

Assume z is a standard normal random variable. Then P(1.05 ≤ z ≤ 2.13) equals _____.

Suppose x is a normally distributed random variable with a mean of 22 and a standard deviation of 5. The probability that x is less than 9.7 is _____.

A property of the exponential distribution is that the mean equals the _____.

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

Suppose 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 ≤ 45) b. P(45 ≤ x ≤ 55) c. P(x ≥ 55) d. x value with 0.20 in the lower tail e. x value with 0.01 in the upper tail

For a standard normal distribution, the probability of obtaining a z value of less than 1.6 is _____.

Whenever the probability is proportional to the length of the interval in which the random variable can assume a value, the random variable follows a(n) _____ distribution.

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit, Independence, and Multiple Proportions

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Decision Analysis

Sample Survey

Filters

Exam 6: Continuous Probability Distributions

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

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

The assembly time for a product is uniformly distributed between 6 and 10 minutes. The probability of assembling the product between 7 and 9 minutes is _____.

The highest point of a normal curve occurs at _____.

About 95.4% of the values of a normal random variable are within approximately how many standard deviations of its mean?

A normal probability distribution _____.

Suppose x is a normally distributed random variable with a mean of 12 and a standard deviation of 3. The probability that x equals 19.62 is _____.

Given that z is a standard normal random variable, what is the value of z if the area to the right of z is .1401?

The standard deviation of a standard normal distribution _____.

For a standard normal distribution, a negative value of z indicates _____.

For a continuous random variable x, the probability density function f(x) represents _____.

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

Assume z is a standard normal random variable. Then P(1.05 ≤ z ≤ 2.13) equals _____.

Suppose x is a normally distributed random variable with a mean of 22 and a standard deviation of 5. The probability that x is less than 9.7 is _____.

A property of the exponential distribution is that the mean equals the _____.

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

Suppose 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 ≤ 45) b. P(45 ≤ x ≤ 55) c. P(x ≥ 55) d. x value with 0.20 in the lower tail e. x value with 0.01 in the upper tail ​

For a standard normal distribution, the probability of obtaining a z value of less than 1.6 is _____.

Whenever the probability is proportional to the length of the interval in which the random variable can assume a value, the random variable follows a(n) _____ distribution.

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Inferences About Population Variances

Tests of Goodness of Fit, Independence, and Multiple Proportions

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Decision Analysis

Sample Survey

Filters

Suppose 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 ≤ 45) b. P(45 ≤ x ≤ 55) c. P(x ≥ 55) d. x value with 0.20 in the lower tail e. x value with 0.01 in the upper tail