A card is drawn randomly from 85 identical cards numbered from 1 to
85, find the probability that the number on the drawn card is NOT a
The probability of event occurring is equal to the number of favorable outcomes divided by the total number of possible outcomes in the sample space, .
In this case, event is drawing a card that is a perfect square, so event is drawing a card that is not a perfect square. The cards that are perfect
squares are 1, 4, 9, 16, 25, 36, 49, 64, and 81, so these are the favorable outcomes for event . Find the probability of event as follows:
The events and are complementary, so the sum of their probabilities is equal to 1. Now use this fact to find the probability of .
Thus, the probability of drawing a card that is not a perfect square is .