Question

How many numbers are there between 99 and 1000 such that the digit 8 occupies the unit's place?

Answer 1

Hundred's place can be filled up with any digit from 1–9,1–9,barring 88, i.e. 8 such digits. Units place can be filled up with any digit from 00–9,–9, barring 88 i.e. 9 such digits. This gives us 99∗8=72∗8=72numbers, with 88 in tens place. This gives us 8∗9=728∗9=72 numbers, with 88 in units place.