The sum of all odd numbers form 1 to 99

The sum of all the odd numbers from 1 to 99 is easy to explain. Take the first and last numbers, 1 and 99. They add up to 100. Then take the next two numbers, 2 and 98. They also add up to 100. If you keep doing this, you will get 25 numbers that can be multiplied by 100. So the answer is 2,500.

Ac equals 35 cm long