# A number is chosen at random among the first 120 natural numbers. The probability of the number chosen to be a multiple of 5 or 15 is

1) 1/5

2) 1/8

3) 1/24

4) ⅙

Solution: Option (A) 1/5

Given that, there are 120 natural numbers and one number is chosen at random. Hence, the total cases = 120C1 = 120

Favourable outcomes (a number should be a multiple of 5 or 15) = {5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120}

Hence, the total number of favourable outcomes = 24

Therefore, the required probability = 24/120 = ⅕