AP Statistics Unit 6

A company states that 2% of its computers are returned for defects.  We take a sample of 100 computers to find the probability of 10 being defective.  Is this a binomial distribution?

• No because there is not a fixed number of trials.

• No because their are more than 2 outcomes.

• Yes since there are a fixed number of independent trials, outcomes in 2 categories, and the probability of defect is constant.

• No since computers would not be independent.

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

If A and B are mutually exclusive, which statement below must be true?

• P(A∩B) = 0

• P(A|B) = 0

• P(A∪B) = 0

• P(A) + P(B) = 1

What is the probability that a randomly selected girl speaks French?

• 2.14

• .24

• .4

• .8571

In your top dresser drawer are 6 blue socks and 10 grey socks, unpaired and mixed up. One dark morning you pull two socks from the drawer (without replacement, of course!). What is the probability that the two socks match?Hint: try a tree diagram, but be careful with probabilities on the second column of branches.

• 0.075

• 0.375

• 0.450

• 0.500

If 10 is added to every value in a set of data, what will happen to the value of the mean?

• it will increase by 10

• it will decrease by 10

• it will stay the same

• it will both increase and decrease

If 10 is added to every value in a set of data, what will happen to the value of the standard deviation?

• it will increase

• it will decrease

• it will stay the same

• it will both increase and decrease

In a survey of men in the United States (ages 20-29), the mean height was 69.6 inches with a standard deviation of 3.0 inches. Find the minimum height in the top 22%.

• 69.37 in 

• 67.58 in 

• 73.12 in 

On an eight question multiple choice quiz with 4 answers for each question, what is the probability of guessing and getting 6 correct answers?

• .004

• .109

• .003

• .9996

The table represents the probability of guessing correct on a 5 question true-false quiz.  Find the probability for at least 4 questions correct.

• .03125

• .15625

• .3125

• .1875