Dialing a telephone number an oldman forgets the last two digits remembering only that these are different dialed at random. The probability that the number is dialed correctly is

I think the is 1/90As number can be from 00 to 99That is 100 numbers but the two numbers were different so so we remove 00,11,22,33,44,55,66,77,88,99, from those hundred numbersSo total number of outcomes is 90Since only one is correct so probability of right number is 1/90

Approved