Question

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

Answer 1

Let the digits at the tens and the ones place be x and y, respectively. So, the two digit number is 10x + y.
Now,
x + y = 9 .....(i)
Also,
10x + y + 27 = 10y + x
⇒ 9x − 9y = −27
⇒ x − y = −3 .....(ii)
Adding (i) and (ii), we get
2x = 6
⇒ x = 3
Putting x = 3 in (i), we get
3 + y = 9
⇒ y = 6
Thus, the required number is 10 × 3 + 6 = 36.

Hence, the correct answer is option (d).