Updated: 2024-02-28 16:07:02
How to divide any number by 5 in 2 seconds or less using a math trick
Updated: 2024-02-27 20:27:24
There are a lot of puzzles where you need to guess something asking only yes-or-no questions. In this puzzle, there are not two but three possible answers. Puzzle. Mike thought of one of three numbers: 1, 2, or 3. He is allowed to answer “Yes”, “No”, or “I don’t know”. Can Pete guess the number […]
Updated: 2024-02-23 09:46:46
Use this math trick to square numbers from 50 to 59 in 2 seconds or less
Updated: 2024-02-22 15:07:37
Find the sum of consecutive odd numbers in 4 seconds or less
Updated: 2024-02-22 15:05:45
Here is how to find the sum of consecutive even numbers in 4 seconds or less using a trick.
Updated: 2024-02-22 09:25:50
Use this trick to divide any 3-digit number by 99 in 3 seconds or less
Updated: 2024-02-21 15:28:21
Use this trick to find 5 percent of any number in 4 seconds or less.
Updated: 2024-02-21 01:24:47
I rarely post physics puzzles, but this one is too good to pass on. Puzzle. A wireframe icosahedron is assembled so that each of its edges has a resistance of 1. What is the total resistance between opposite vertices of the icosahedron? While we are at it, another interesting question would be the following. Puzzle. […]
Updated: 2024-02-16 09:22:58
Use this trick to multiply a two-digit number by 101 in one second or less
Updated: 2024-02-14 20:19:19
Have you ever heard of ikigai? The Japanese concept which gives four simple requirements for a happy career: I often think about it for myself and for my students. Is this good advice for finding a career path? I like that ikigai separates the first two requirements: passion and gift. Many of my students do […]
Updated: 2024-02-13 16:26:40
How to solve a system of two linear equations quickly (in 15 seconds or less!)