Let us assume, x and y are the two digits of the two-digit number
Therefore, the two-digit number = 10x + y and reversed number = 10y + x
Given:
x + y = 9 -------------1
also given:
10x + y - 27 = 10y + x
9x - 9y = 27
x - y = 3 --------------2
Adding equation 1 and equation 2
2x = 12
x = 6
Therefore, y = 9 - x = 9 - 6 = 3
The two-digit number = 10x + y = 10*6 + 3 = 63