Question

When you reverse the digits in a certain two-digit number you increase its value by 27. find the number if the sum of its digits is 15?

Answer 1

The unknown number is 69.

*If you reverse 69, it would be 96. Thus, increasing its value by 27. 
96 - 69 = 27

*The sum of its digits 6 and 9 equals to 15.