Quiz #3 (Answer any 10 problems) 2 points each

Write "SKIP" for the problem you are skipping

1. If a penny is tossed four times and comes up heads all four times, the probability of heads on the fifth trial is

a. 0

b. 1/32

c. 0.5

d. larger than the probability of tails

e. None of the above

2. Two events are mutually exclusive

a. if their intersection is 1

b. if they have no sample points in common

c. if their intersection is 0.5

d. both a and c are correct

e. None of the above

3. Given that event E has a probability of 0.25, the probability of the complement of event E(E')

a. cannot be determined with the above information

b. can have any value between zero and one

c. must be 0.75

d. is 0.25

e. None of the above

4. Of five letters (A,B,C,D, and E), two letters are to be selected at random. How many possible selections are there?

a. 20

b. 7

c. 5!

d. 10

e. 22

5. If A and B are independent events with P(A) = 0.5 and P(B) = 0.3, then P(AUB) = ?

6. Using #5 P(A l B) =? (A GIVEN B)

7. Using #5 If A and B are mutually exclusive, P(A INTERSECT B) = ?

8. Using #5 If A and B are mutually exclusive, P(AUB)=?

9. A lottery uses 4 urns containing chips 0 to 9. One chip is selected at random from each urn. How many sample points are in the sample space?

10. A die is tossed twice. What is the probability of obtaining 6 dots both times?

11. If P(A) = 0.3 and P(AUB) = .88 and P(A intersect B) = .12, then P(B)= ?

***********************************************************************************************

Remember P(AUB) = P(A) +P(B) - P(A intersect B)

P(A l B) = P(A intersect B)/P(B)

Independent Events: P(A intersect B) = P(A)*P(B)

P(A) = 1 - P(A**C)where A**C means complement of A