Q: A four figure number is formed of the figures 1, 2, 3, 5 with no repetitions. The probability that the number is divisible by 5 is

(A) 3/ 4

(B) 1/ 4

(C) 1/8

(D) None of these

**Click to See Answer : **

Ans: (B)

Sol: The total number of ways in which four-digit numbers can be formed, is 4! = 24. A number is divisible by 5 if at unit’s place, we have 5. Therefore unit’s place can be filled in one way and the remaining 3 places can be filled with the other digits in 3! ways. Hence the total number of numbers divisible by 5 is 3!=6

The required probability = 6/24 = 1/4 .

The required probability = 6/24 = 1/4 .