Question

On the first book shelf there are 123 books. On the second shelf there are 81 books. How many books should be moved from the first shelf to the second one to have the same number of books on each book shelf? How many books will be the on each shelf in this case?

Answer 1

21

Explanation:

First we need to find the midpoint.

To find the mid point:

(123+81)÷2=102

So, we need to get both shelfs 102

123-102=21

Answer 2

21 books need to be moved

Explanation:

123+81=204

204/2=102

So there needs to be 102 books on each shelf.

123-102=21

So 21 books need to be moved from the first shelf.