A bag contains 7 red chips and 10 blue chips. Two chips are selected randomly without replacement from the bag. What is the probability that both chips are red?

3 answers

Once the first red chip has been picked, there are only 16 total chips and 6 red chips remaining.

To find the probability that both (all) events occur, you need to multiply the probabilities of the individual events.

7/17 * 6/16 = ?
A box contains 25 yellow, 28 green and 38 red jelly beans.
If 13 jelly beans are selected at random, what is the probability that:

a) 5 are yellow?
b) 5 are yellow and 7 are green?
c) At least one is yellow?
the anwser is 4