Question

A number of 2 digit is such that its unit digit is x and ten's digit is (12-x).when the digits are reversed the number is increased by 54.Find the number

Answer 1

The no at the tens digit will be 12-x
And the no at ones digit will be x
Therefore,
The original no is = 10(12-x)+x
=120-10x+x
=120-9x
Now,
The digit at the tens place of reversed number be x
And the digit at the once place of reverse number be 12 - x
Therefore,
The riversed number =10x+(12-x)
= 9x+12
A/q
(120-9x)+54=9x+12
=>174-9x=9x+12
=>174-12=9x+9x
=>162=18x
=>x=162/18
=>x=9
Therefore
Original number=120-9×9
=120-81
Answer=39