Multiple choice

If the digits of a two-digit number interchange places and the new number is added to the original number, then the resulting number will be divisible by

  1. 3

  2. 5

  3. 9

  4. 11

  5. None of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let the ten's digit be x and the unit's digit be y. Then, the number = 10x + y. The number obtained by interchanging the digits = 10y + x (10x + y) + (10y + x) = 11(x + y), which is divisible by 11.