Question 1

The distribution of probabilities for each outcome of a random variable that sums to 1.00 is called a

Accepted Answer

A)  random variable
B)  probability distribution
C)  conditional probability
D)  sample space B

Question 2

The probability of a team having a sellout crowd is p = .45.The probability of having a sellout crowd and the team winning is p = .32.Hence,the probability of a team winning,given that they have a sellout crowd,is

Accepted Answer

A)  p = .71
B)  p = .77
C)  p = .14
D)  There is not enough information to answer this question. A

Question 3

A distribution of probabilities for random outcomes of a bivariate or dichotomous random variable is called a

Accepted Answer

A)  binomial probability distribution
B)  distribution of expected values
C)  random variable distribution
D)  mathematical expectation A

Question 4

Which rule states that when two outcomes are independent,the probability that these outcomes occur together is the product of their individual probabilities?

Accepted Answer

A)  additive rule
B)  multiplicative rule
C)  both A and B
D)  none the of above

Question 5

Suppose that the probability that any child of alcoholic parents becomes alcoholic is p = .16.Assuming independent outcomes,the probability that two children of alcoholic parents will be alcoholic equals

Accepted Answer

A)  .16
B)  .32
C)  .25
D)  .03

Question 6

The probability of an outcome can be any positive value.

Accepted Answer

A) True 
 B)False

Question 7

The mean of a probability distribution is called the

Accepted Answer

A)  expected value of the mean
B)  mathematical expectation
C)  both A and B
D)  none of the above

Question 8

The multiplicative rule is used for independent outcomes.

Accepted Answer

A) True 
 B)False

Question 9

The probability distribution is p = .24,.16,.40,and .20 for a random variable with outcomes equal to 0,1,2,or 3,respectively.In this example,the expected value of the mean is greater than two.

Accepted Answer

A) True 
 B)False

Question 10

For mutually exclusive outcomes,one or the other outcome can occur (Outcome A or Outcome B),but not both outcomes (Outcome A and Outcome B).

Accepted Answer

A) True 
 B)False

Question 11

A researcher determines that the relative frequency of participants with prescription glasses is .23.Hence,the probability that participants will wear prescription glasses must be greater than p = .23.

Accepted Answer

A) True 
 B)False

Question 12

The probability of a college student being employed is p = .35.The probability of a student being employed and dropping out of college is p = .20.Hence,the probability of a student dropping out of college,given that he or she is employed,is

Accepted Answer

A)  p = .07
B)  p = .57
C)  p = .55
D)  There is not enough information to answer this question.

Question 13

The probability that a parent rewards a child with a dessert for eating a healthy meal is .07.Assuming independent outcomes,the probability that two parents reward their child's healthy eating equals

Accepted Answer

A)  .07
B)  .14
C)  .05
D)  .005

Question 14

A researcher determines that the probability of missing class among students at a local school is p = .16.Assuming that the school has 300 students enrolled,how many students can we expect to miss class on a given day? Hint: This is a binomial probability distribution.

Accepted Answer

A)  252 students
B)  48 students
C)  16 students
D)  There is not enough information to answer this question.

Question 15

If the standard deviation of a probability distribution is 9,then the variance is

Accepted Answer

A)  3
B)  9
C)  81
D)  unknown

Question 16

Bayes' theorem is most often applied to situations in which probability is not calculated.

Accepted Answer

A) True 
 B)False

Question 17

A researcher records the number of job openings among small businesses.She finds that the probability that a small business has 0 job openings is p = .22;1 job opening is p = .45;2 job openings is p = .08;and 3 job openings is p = .25.What is the probability that a small business has at least 2 job openings?

Accepted Answer

A)  .08
B)  .25
C)  .33
D)  .67

Question 18

A researcher finds that 20 of 120 students failed an exam.In this case,the probability of failing this exam was

Accepted Answer

A)  .14
B)  .17
C)  .20
D)  unknown

Question 19

The mean of a binomial distribution is the product of the number of trials (n)times the probability of the outcome of interest on an individual trial (p).

Accepted Answer

A) True 
 B)False

Question 20

The expected value of a random variable can be thought of as a "long-term" mean.

Accepted Answer

A) True 
 B)False

Exam 5: Probability

The distribution of probabilities for each outcome of a random variable that sums to 1.00 is called a

The probability of a team having a sellout crowd is p = .45.The probability of having a sellout crowd and the team winning is p = .32.Hence,the probability of a team winning,given that they have a sellout crowd,is

A distribution of probabilities for random outcomes of a bivariate or dichotomous random variable is called a

Which rule states that when two outcomes are independent,the probability that these outcomes occur together is the product of their individual probabilities?

Suppose that the probability that any child of alcoholic parents becomes alcoholic is p = .16.Assuming independent outcomes,the probability that two children of alcoholic parents will be alcoholic equals

The probability of an outcome can be any positive value.

The mean of a probability distribution is called the

The multiplicative rule is used for independent outcomes.

The probability distribution is p = .24,.16,.40,and .20 for a random variable with outcomes equal to 0,1,2,or 3,respectively.In this example,the expected value of the mean is greater than two.

For mutually exclusive outcomes,one or the other outcome can occur (Outcome A or Outcome B),but not both outcomes (Outcome A and Outcome B).

A researcher determines that the relative frequency of participants with prescription glasses is .23.Hence,the probability that participants will wear prescription glasses must be greater than p = .23.

The probability of a college student being employed is p = .35.The probability of a student being employed and dropping out of college is p = .20.Hence,the probability of a student dropping out of college,given that he or she is employed,is

The probability that a parent rewards a child with a dessert for eating a healthy meal is .07.Assuming independent outcomes,the probability that two parents reward their child's healthy eating equals

A researcher determines that the probability of missing class among students at a local school is p = .16.Assuming that the school has 300 students enrolled,how many students can we expect to miss class on a given day? Hint: This is a binomial probability distribution.

If the standard deviation of a probability distribution is 9,then the variance is

Bayes' theorem is most often applied to situations in which probability is not calculated.

A researcher finds that 20 of 120 students failed an exam.In this case,the probability of failing this exam was

The mean of a binomial distribution is the product of the number of trials (n)times the probability of the outcome of interest on an individual trial (p).

The expected value of a random variable can be thought of as a "long-term" mean.