Question

A bag contains 25 cards numbered from 1 to 25. A card is drawn at random from the bag. Find the probability that the number on the drawn card is:

(i) divisible by 3 or 5

(ii) a perfect square number

Answer 1

Total number of cards = 25

(i) Numbers divisible by 3 or 5 are 3, 5, 6, 9, 10, 12, 15, 18, 20, 21, 24 and 25.

Total favourable number of cards = 12

Probability that the number on the drawn card is divisible by 3 or 5 = `"Total favourable number of cards"/"Total number of cards"=12/25`

(ii) Perfect square numbers are 1, 4, 9, 16 and 25.

Total favourable number of cards = 5

Probability that the number on the drawn card is a perfect square number = `"Total favourable number of cards"/"Total number of cards"=5/25=1/5`