1. Two 4-sided dice are tossed 10 times and the sum of the "down" faces is noted.

a. What is the probability that the sum of 4 occurs at most two times? Leave your answer as a percent rounded to one decimal place.

b. What is the expected number of times a sum of three should occur?

2. A drawer contains 5 pairs of green socks, 3 pairs of black socks, and 4 pairs of red socks. The 12 pairs of socks are jumbled together in one drawer, but each sock is still attached to its mate. You reach into the drawer and pull out 3 pairs of socks, one at a time, without putting any back.

a. What is the probability that you get 2 pairs of green socks? Leave your answer as a fraction in lowest terms.

b. What is the expected number of pairs of green socks?