posted by jane .
A bag contains ﬁfty slips (small pieces of paper) with the numbers 1, 2, . . . , 50 written on them
(One number on each slip!). Your friend writes down ten numbers from 1, 2, . . . , 50 on a sheet
of paper, and then you draw—without replacement—twenty slips randomly from the bag, and
look at the numbers drawn.
1. What is the sample space?
2. What is the probability that all the numbers which your friend wrote down also appear
among the drawn slips?
3. What is the probability that none of your friend’s numbers is drawn?
4. What is the probability that exactly half of your friend’s numbers are drawn?