Question

The digits of a two-digit number differ by 3. If digits are interchanged and the resulting number is added to the original number, we get 121. Find the original number.

Answer 1

Answer:

Let the digit at tens place be x and unit place be y

original number = 10x+y

x-y=3........(i)

Number obtained by interchanging the digits = 10y+x

a/q

(10y+x)+(10x+y)=121

10y+x+10x+y=121

11x+11y=121

x+y=121÷11=11.........(ii)

On adding (i)and(ii) we get,

2x=14

x=14÷2=7

on putting x=7 in (i) we get,

x-y=3

7-y=3

y=7-3=4