Re:The Party Math Trick
by omgwtf1000 on Tuesday November 30, 2021 @06:22PM
(#29398715)
Here’s one of my favorites - super easy problem that almost everybody gets wrong.
On a piece of paper, write the following numbers as a vertical column:
4000
40
20
30
10
For best results, 4000 should be first and 10 last. Now take a second piece of paper and cover the number list. Ask someone to add the numbers up out loud as you move down the list, uncovering one number at a time starting with 4000. (First you expose the 4000, next the 40, and so on.) In nearly every case the person will call out the following: 4000, 4040, 4060, 4090, 5000. And typically they won’t believe you when you tell them they’re wrong, sometimes even after giving them the paper to redo their math.
On a piece of paper, write the following numbers as a vertical column:
4000
For best results, 4000 should be first and 10 last. Now take a second piece of paper and cover the number list. Ask someone to add the numbers up out loud as you move down the list, uncovering one number at a time starting with 4000. (First you expose the 4000, next the 40, and so on.) In nearly every case the person will call out the following: 4000, 4040, 4060, 4090, 5000. And typically they won’t believe you when you tell them they’re wrong, sometimes even after giving them the paper to redo their math.Edit: formatting