When you reverse the digits of the number 13, the number increases by 18. How many other two-digit numbers increase by 18 when their digits are reversed?

- 5
- 6
- 7
- 8

**Answer**

Let the two-digit number be ab.

When the digits are reveres (ba), the number is increased by 18.

(10a+b) - (10b+a) = 18

a - b = 2

All such numbers that have unit's digit greater than ten's digit by 2.

Numbers are (except 13) 24, 35, 46, 57, 68, 79. So. there are 6 other numbers.

**The correct option is B.**