If a 4 digit number is formed with digits 1, 2, 3 and 5. What is the probability that the number is divisible by 25, if repetition of digits is not allowed?
The total number of four-digit numbers that can be formed = 4!.
If the number is divisible by 25, then the last two digits must be 25.
So the first two digits can be arranged in 2! ways.
Hence, probability = 2!/4! = 1/12
The correct option is A.