age ~9, circa 1786
In a small town in Germany, around the year 1786, a young boy named Carl Friedrich Gauss sat in his classroom. He was about 9 years old.
One day, his teacher — tired and wanting a break — gave the class what he thought would be a very long task: "Add all the whole numbers from 1 to 100!"
The teacher expected this to take the whole lesson. But within seconds, little Gauss walked up and placed his slate on the teacher's desk. The answer? 5,050. Correct! 🎉
How did he do it so fast? He discovered a brilliant pattern — and today, we're going to find it ourselves!
Pick a number n — how about starting small, like 10 or 20? Try to find the sum of all whole numbers from 1 all the way up to n. Take your time, work it out on paper, then check your answer below!
Gauss had a genius shortcut. But first — did you try? 🤔
When your teacher gives you the 6-digit code, type it below to unlock Gauss's brilliant method!
your teacher gives you in class!
Gauss wrote all the numbers from 1 to n, and then wrote them again — but in reverse, from n down to 1. Then he added them together!
Every pair of numbers from the top row and bottom row always adds up to the same number: (n + 1)! And there are exactly n such pairs.
So when you add both rows together, you get: n × (n + 1)
But wait — we added each number twice! So to get the real sum, we just divide by 2!