Question

The Sum of two digits of a two digit number is 7. If digit are interchanged the new number decreased by 2 equal to twice the origimal number. Find the number.

Answer 1

hiii

Sol :

Let x , y are numers of two digit number.

Given that sum of the two digit number = 7

i.e x + y = 7 ---------(1)

According to the question

10y + x – 2 = 2( 10x + y)

19x – 8y + 2 = 0 ----------------(2)

Solving equations (1) and (2) we get

x = 2 and y = 5.