Question

Rashi asked Aarush to take a two digit number and then reverse it. After that, she asked him to add the first number and the reversed number, then finally to divide it by 11. She asked him if there's any remainder left? Aarush's reply will be -

• A. No
• B. No

Answer 1

The correct option is B No

Let's take a two digit number 'ab'. Its general form is:
(10 × a) + (1 × b)
If we will reverse it then the number will become 'ba'. Its general form will be:
(10 × b) + (1 × a)

If we add both the numbers we will get
(10 × a) + (1 × b) + (10 × b) + (1 × a) = 11(a+b)

Hence when 11(a+b) is divided by 11, it does not leave a remainder.