MATH 431 Final: 2014 Math 431 - Seppalainen - Fall Final
Document Summary
431 introduction to the theory of probability fall 2014 final exam. The point total is 100: (40 pts) parts (a) (d) are four quick problems, 10 points each. (a) in one type of state lottery you pick 5 distinct numbers from 1, 2, 3, . Then on saturday night the 5 distinct winning numbers are picked on tv, uniformly at random. What is the probability that you picked exactly two winning numbers? (no simpli cation necessary in the answer. ) (b) suppose we know the following facts about two random variables x and y . E(x 2) = 4, e(xy ) = 2, E(x) = 0, e(y ) = 1, and the correlation coe cient of x and y is 1/3. Find the variance of x and the second moment e(y 2) of y . (c) an urn contains n red balls and n white balls.
