Question

One of the two digit of a two digit number is three time the other digit. If you interchange the digit of this two digit number and add the resulting number to the original number, you get 88. What is the original number?

Answer 1

let two digit number be 10x + y
one of the two digit number is three times the other number so, x=3y...........(1)
if interchange the digit of this two digit number and add the resulting number to original number gives 88 so,
reversed number of 10x+y is 10y+x
then, (10x+y)+(10y+x) = 88
11x+11y=88
11(x+y)=88
x+y=8
but x=3y
so 3y+y=8
4y=8
y=2
x=3*2=6
so the original number is 26 or 62