You are reading "How to add odd numbers from 1 through a 2-digit odd number—Math Tips and Tricks". Today is Friday, 3rd February 2012.

Have you wondered how to solve or add odd numbers from 1 until any 2 digit numbers?

Adding odd numbers is a difficult task if you do not know the tricks on how to shorten the process in solving it or if you do not have any calculating machine. Just imagine adding odd numbers such as 1 + 3 + 5 + 7 + 9. . . through + 99. It is time consuming. To add this manual at a very easy way, just follow the steps below.

Here are the steps to solve it in an easy way without using a calculator or any calculating machine:

Steps:

1.       Choose any 2-digit odd number and then add 1 to it.

Say, find the sum of odd numbers from 1 through 55.

Get the sum 55 + 1 = 56.

2.       Divide the sum of the 2-digit number you chose plus 1 by 2 (or multiply it by 1/2)

Sum in step 1 divided by 2 or 56 ÷ 2 = 28 or 56 (½) = 28

3.       Multiply the result in step 2 by itself or square it.

The result of step 2 is 28; multiply it by itself or square it (28 X 28 or 2828) to get 784 which is the sum of all odd numbers from 1 through 55.

That is 1 + 3 + 5 . . . + 51 + 53 + 55 = 784

These steps can only be used when you are adding all odd numbers below 100.

Now that you have learned the tricks on how to solve all odd numbers from 1 through 99, it is time for you to share it with your friends or subscribe for the next tricks. You can also read our previous Math tip.