Question

The sum of two digit number is15.the number obtained by reversing the order of digits of the given number exceeds the given number by 9.find the given number

Answer 1

let two digit number be 10y+x
10y+x=15(first)
by reversing
10x+y=9(second)
from first
x=15-10y
in second
150-100y+y=9
141=99y
y=141/99
y=47/33

Answer 2

let the number is x +y
=10x+y=15
reversed no. is y+x
=10y+x=10x+y+9
10y-y=10x-x+9
9y=9x+9
9 (15/10x)=9x+9
27/2x=9x+9
27/2x-9x=9
13.5x-9x=9
4.5x=9
x=2
y=13