Question

In a two digit number the sum of the digits is 7 if the number with order of digit reversed is 28 greater than twice the unit digit in orginal number

Answer 1

let the original number be 10(7-x)+x
here, x is the ones digit and (7-x) tens digit which is why we multiple it with 10
The reversed number would be 10x+(7-x) we know, 10x+(7-x) =28+2x 10x7-x=28-2x
10x-2x-x= 28-7
7x=21
x=3
hence original number is 10(7-x)+3=45