Question

A number consists of two digits whose sum is five when the digits are reversed the number becomes greater by 9 find the number

Answer 1

x+y=5−−−(1) if the number is 10x+y;then 10y+x−(10y+y)=99y - 9x = 9 or y−x=1−−−−(2) on solving both equation (1) and (2) we get,y = 3 and x = 2 Hence the no. is 23