Question

a number consist two digit whose sum is 8. if 18 is added to the number the digit interchange their place. find the number.

Answer 1

Let the numbers be 10x and y

Acc. to question, 10x + y = 8

and when 18 is added to the number
then, 10x + y + 18 = 10y + x

9x - 9y = -18
after reducing it,
x - y = -2

So, 10x = 8 - y
x = 8 - y/ 10

On putting the value of x,
8-y/10 - y = -2
Therefore, y = 28/11

x-y = -2

x - 28/11 = -2

Therefore, x = 6/11
Hope it helps you.