A cereal maker places a game piece in each of its cereal boxes. The probability of winning a prize ...

A cereal maker places a game piece in each of its cereal boxes. The probability of winning a prize in the game is 1 in 4. Find the probability that you (a) win your fist prize with your fourth purchase, (b) win your prize with first, second, or third purchase, and (c) do not win a prize with your first four purchases.