How good is your math? Can you do better than 8 year old Fredrick Gauss?
The Question: What is the sum of all of the whole numbers between 1
and 1,000 inclusive?
Show all of the necessary calculations on a single sheet of paper.
The Answer 500,500
The Workings: Pair the numbers at the extreme ends of the range:
1 + 1,000 = 1,001
Move up one at the lower end, and down one at the
higher end:
2 + 999 = 1,001
Continue moving away from the ends of the range, one
number at a time;
3 + 998 = 1,001
At the mid point, you will converge:
500 + 501 = 1,001
Thus there are 500 pairs, each of which adds to 1,001.
The answer is 500 times 1,001, or 500,500.
The History
Allegedly this activity was set by a teacher as work to keep the class busy.
Unfortunately in 1885, it proved inadequate. One student, 8 year old Frederick Gauss, solved the problem in seconds. He later went on to become a significant mathematician.
<Thanks to Duard Worthen for this information. He saw the article "Great games, but when does the learning start?" and e-mailed me the name of the mathematician.