Question

10. The sum of the digits of a two digit number is 9. If 27 is added to it, the digits of the numbers
get reversed. The number is
(a) 36
(b) 72
(c) 63 (d) 25​

Answer 1

Let the number be xy

x+y=9...............(1)

(10x+y)+27=10y+x

10x-x+y-10y=-27

9x-9y=-27

x-y=-3................(2)

add equation 1 and 2

we get

x=3

substitute it in eq 1

y=6

so the number is 36