Image: Carl Frederick Gauss, known as the greatest mathematician of all time.

Many people already know the answer and many do not. So I will not answer directly. Rather I am narrating the answer through a story

The great mathematician Carl Friedrich Gauss was a brilliant genius from an early age. He was already hinting that something very big would happen in the future. He would sit down before the teacher finished the math and insist on giving the teacher some more problems. Once annoyed the teacher gave him a challenging problem. I thought this time Gauss could be seized for a while. What was the problem?

The reader is right. You are here to find the answer to this question. So this question is also a little famous. Let's finish the story.

The teacher asked Gauss to find the sum of the numbers from 1 to 100. He thought it would take a little time for Gauss to breathe a sigh of relief.

But the rules are left! Did the teacher know who he was challenging? It doesn't matter to this boy whether he will be the best mathematician of all time.

Gauss got into the problem. He saw that adding 1 + 2 + 3 + 6 in this way was equivalent to working like a bull. He bit the pen, closed his eyes and thought for a while and got an idea in a moment. He wrote in his notebook:

Suppose, 1 + 2 + 3 + ....... + 100 = x

So, 100 + 99 +98+........+1=x

So if I add these two equations, then that stands for,

101 + 101 + 101 + ....... + 101 = 2x

There are a total of 100 posts with 101 such. So

2x = 101 × 100 = 10100

That is, x = 10100/2 = 5050

Gauss ran to the teacher and asked her to give him another problem. The teacher is surprised. It is not supposed to be solved so fast. Seeing Gauss's solution, the teacher's eyes widened. He could do nothing but raise his glasses to his forehead and look at the little Gauss with his hands on his cheeks.