Question

A no consist of two digits whose some is 8 , if 18 is add to the no, it's digit are reversed find the no

Answer 1

Let the Ten's place digit be x and unit place digit be 8 - x ( ∵ sum of digits = 8)

Two digit number is of form 10 (Ten Place Digit) + Unit Place Digit

∴ Two digit number formed = 10 (x) + (8 - x)

                    = 10x + 8 - x

                   = 9x + 8

Number formed by reversing the digits = 10 ( 8 - x ) + x

                   = 80 - 10x + x

                   = 80 - 9x

According to question

Original Number + 18 = Number obtained by reversing the digits

∴ 9x + 8 + 18 = 80 - 9x

18x = 80 - 26

18x = 54

x = 3

∴ Original  number = 9x + 8 = 35

35 is the desired number