Question

Two urns contain white balls and yellow balls. The first urn contains 2 white balls and 7 yellow balls and the second urn contains 10 white balls and 4 yellow balls. A ball is drawn at random from each urn. What is the probability that both balls are white?

Answer 1

The first one has 2 white balls out of 9 total.
The probability of pulling a white ball from it is 2/9 . (about 22.2%)

The second one has 10 white balls out of 14 total.
The probability of pulling a white ball from it is 10/14. (about 71.4%)

The probability of both of these things happening is

(2/9) x (10/14) = 20/126 = 10/63 = about 15.9% (rounded)