Finite Math Test #2 Nov. 13, 2000 A Track R. Hammack Name: ________________________ Score: _________

(1) Suppose that A and B are subsets of a universal set U, and that n( U ) = 50, n(A) = 10, n(A ∪ B) = 20, and n(A ∩ B) = 3. Supply the following information.

(a) n( A' ) =

(b) n( B ) =

(c) n( A' ∪ B ) =

(d) n( A' ∩ B ) =

(2)

(a) In how many ways can you choose a committee of 4 people from a group of 10 people?

(b) From a group of 10 people, you select a president, a vice-president, a secretary and a treasurer. In how many ways is this possible?

(3) Suppose A and B are events, and P(A) = 1/2, P(B) = 1/3, and P(A ∪ B) = 2/3.
Are A and B independent, dependent, or is there not enough information given to say for sure? Explain.

(4) One card is drawn off a 52-card deck. What is the probability that it is...

(a) a heart or a King?

(b) a heart and a King?

(c) neither a heart nor a King?

(d) a heart, given that it's also a King?

(5) A coin is tossed 6 times. What is the probability that ...

(a) the first 2 tosses are heads?

(b) exactly 2 of the 6 tosses are heads?

(c) less than 2 of the 6 tosses are heads?

(d) the first 2 tosses are heads or the last toss is a head?

(6) At a certain college, 40% of the students are male, and 60% are female. Also, 20% of the males are smokers, and 10% of the females are smokers.

(a) A student is chosen at random. What is the probability that the student is a male nonsmoker?

(b) A student is chosen at random. If the student is a smoker, what is the probability that the student is female?