Question

The sum of digits of a two digit number is 7. If the digits are reversed and the reversing number is decreased by2 twice the original number obtained

Answer 1

EXPLANATION

• GIVEN

The sum of two digit number is = 7

x + y = 7 .... (1)

if digit are reversed and reversing number is

decreased by 2 twice the original number

10x + y - 2 = 2(10y + x)

8x - 19y = 2 ..... (2)

TO FIND THE ORIGINAL NUMBER

multiply equation (1) by 19 we get,

x = 5

put x = 5 in equation (1) we get,

5 + y = 7

y = 2

original number = 10y + x

10(2) + 5 = 25 = ANSWER