Question

sum of the digits number is 9.when we interchange the digits,it is found that the resulting new number is greater than the original number by 27.what is the two digit number?

Answer 1

Let’s say x is the unit digit and y is the tenth digit.

y+x = 9 -> y=9-x

10x+y = 10y+x+27

10x+9-x = 10(9-x)+x+27

10x+9-x = 90–10x+x+27

18x = 108

x = 6

so y = 3

let’s check

63 - 39 =27

27 = 27 (correct)