King Fahd University of Petroleum & Minerals
Department of Mathematical Sciences
Stat. 319, Quiz # 2 (semester 042)
SECTION:
INSTRUCTOR: MUSAWAR MALIK
NAME:
ID #:
1. Suppose that you are in a poorly maintained boat with two engines. What is the
probability that at least one engine fails, when:
P (left engine fails) = .40
P (right engine fails) = .30
P (both engines fail) = .12
2. Suppose that 100 students are surveyed about their courses. Thirty of them are
taking a foreign language and 40 are taking a math course. Of these, 15 are taking
both a foreign language and a math course.
a. Fill in a joint probability table using the above data.
b. What is the probability that one of these students selected randomly is taking a
foreign language OR a math course?
c. What is the probability that one of these students selected randomly is taking a
foreign language given that he is taking a math course?
3. Suppose that you have a long list of names. You are told that if you pick a random
name , there is a .60 probability that person is brown eyed. Assuming this is true,
if you draw two names,
a. What is the probability that they are both brown-eyed?
b. What is the probability that neither is brown-eyed?
c. What is the probability that at least one is brown-eyed?
d. What is the probability that one is brown-eyed and the other is not?