Alice has a bowl with 8 balls. Three of the balls are white and the rest are black. Bob picks two balls from the bowl at random. What is the probability that both balls are white?
Before Bob's first pick, there are 3 white balls and 5 black balls.

The probability of picking a white ball is 3/8.

After that, there are 2 white balls and 5 black balls.

The probability to pick another white balls is 2/7

Since the picks depend on each other we can multiply them to get the final probability of (3/8)*(2/7) = 6/56 = 3/28