Question

Question #dd09d

Answer 1

875

Explanation:

The sum of the first `n` odd numbers is equal to `n^2`.

In order to find the sum of the odd numbers between `10` and `60`, just find the sum of the odd numbers below `60` and subtract the sum of the odd numbers below `10`.

Since there are `30` odd numbers below `60` (the sum of these odd numbers would be `30^2`) and `5` odd numbers below `10` (the sum of these odd numbers would be `5^2`), the answer is `30^2-5^2=900-25=875`.