Question 1

A road stop has been established during a busy holiday weekend. Historical data has that 12% of drivers will not be wearing their seatbelt. 10 drivers are stopped. What is the probability that at all 10 drivers are wearing their seatbelt?

Group of answer choices

(0.12)^10

1(0.12)^10

(0.88)^10

1(0.88)^10

Question 2

A Material Review Board is being formed to review discrepant material. The Engineering Manager will chair the board. 2 engineers will be selected out of 8 available to also be on the board. How many different ways (combinations) can these engineers be selected?

Group of answer choices

36

56

504

84

28

Question 3

Which of the following is not true of the Poisson distribution?

Group of answer choices

Events which occur can be counted, but events which do not occur cannot be counted.

Events are counted within a defined unit.

The population and sample size must be defined.

None of the above. (All of the above are true.)

Question 4

1000 parts are produced in a batch on a machine of which 15% in the batch (150 parts) are known to be defective. A sample of 25 parts is taken from the batch. To get the probabilities of getting a given number of defective units in the sample, which distribution should be used?

Group of answer choices

Poisson because I can count the defective units that are there, but not count the ones that are not there.

Hypergeometric because I have a small finite population from which the sample is drawn and the probability of being defective are constant with each part inspected.

Binomial because I have a constant defective rate and parts can be either defective or not defective.

Binomial estimation of hypergeometric because the change in the probability of being defective is very small as each part is taken from the sample for inspection.

Question 5

In a dice game, a player must roll a 1 or a 6 to win a point. Out of 10 rolls of a fair die, we want to know the probability of a player winning 4 points. To determine this, which distribution would be used?

Group of answer choices

Poisson as we can count winning rolls but cannot count the losing rolls

Binomial as we can define success as rolling a 1 or 6 and failure as rolling 2,3,4 or 5

Hypergeometric as the probabilities change with each roll of the dice.

Either hypergeometric or the binomial estimation of hypergeometric could be used.