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

The total number of ways in which four-figure 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 in3! ways. Hence, total number of numbers divisible by 5 is 3! = 6. So, the required probability is 6/24 =1/4