Probstat/homework 1

Basic problems

1. Work on problems 1, 3, 5, 7, 9, and 10 in Counting section in week2 practice 1.

Challenging problems

1. We are tossing N different balls into N bins. Each ball is equally likely to land in any bins. What's the probability that there is no empty bins? (I.e., empty bins are those with no balls landed on.)