Question 23
The rooms in a hotel are each numbered with a three digit number. The first digit determines the floor and the last two digits - the number of the room on the floor; e.g. room 125 is room 25 on the first floor. The hotel has 5 floors (from 1 to 5) and 35 rooms on each floor, i.e. on the first floor you have room numbers 101 to 135, etc. How many times does the digit 2 appear in all room numbers of that hotel?