I randomly choose an integer from 1to100, inclusive. If Mary chooses a multiple of 4, what is the probability she will choose a perfect square? Express your answer as a common fraction.

Question

Please help ASAP

Answer 1

Between 1 and 100 there are 25 multiples of 4. Those that are perfect squares are multipliers of 4 which are also perfect squares, since 4 is a perfect square itself. The perfect squares up to 5^2 are 1, 4, 9, 16, 25. So if Mary chooses 4, 16, 36, 64 or 100, that is 5 out of 25 possibilities=1/5.