Curated Video
MATHS PROBLEM STUMPING EVERYONE! Fraction Of Square Shaded
Mathematician Ed Southall, from the University of Huddersfield, created a stir when he tweeted this problem (@solvemymaths). The problem was covered in "The Daily Mail" and "The Sun." In this video I present one way to solve it. My blog...
Curated Video
Seemingly Impossible 7th Grade Math Riddle - The Coded Table
Thanks to George who sent me this problem (created by 7th grade math teacher Ms. V)! There is a table in the video. The numbers in the first column are increased by the same percentage to give the numbers in the second column. But the...
Curated Video
Why Facebook Invented A New Time Unit Explained With Math
On January 22, 2018, Facebook Open Source tweeted to announce the "flick," a unit of time to help sync various video frame rates and audio sampling frequencies. The media loved the story and some explained the idea. But no one explained...
Curated Video
AMAZING CIRCLE ILLUSION! Optical Illusion Explained With Math
This incredible optical illusion shows how circular motion can result from linear motion! The reason we see the circle has to do with high school geometry. I explain why and give a formal mathematical proof in the video. My blog post for...
Curated Video
Can You Solve The Three Erupting Geysers Riddle?
Thanks to Brian Galebach who created and sent me this problem! You arrive at a park where geysers A, B, and C erupt at intervals of precisely 2, 4, and 6 hours, respectively. Each started erupting independently at a random time in...
Curated Video
Make A 9x9 Magic Square! Learn The Ancient Chinese Algorithm (Lo Shu Square)
Magic squares are arrangements of numbers where every row, column, and diagonal adds up to the same number. The ancient Chinese developed a geometric method to create 3x3 magic squares. Remarkably, they generalized the method to create a...
Curated Video
Change Four Dots To Make This True! Most People Fail
Thanks to Professor Peer Johannsen at Pforzheim University for creating this puzzle! Color four dots blue or erase four blue dots to make a valid equation: (10 + 11)(10 - 11) = 100 + 1! Watch the video for the amazing answer! The 71...
Curated Video
GENIUS Test Divisibility By 7 - Graph Visualization
This graph will tell you if a number is divisible by 7. Start at the circle YES. Move a number of black arrows equal to the first (leftmost) digit of the number. Then move one green arrow to get to the next digit. Repeat this for each...
Curated Video
The Seemingly IMPOSSIBLE Cyclist And Motorcycles Riddle
Thanks to Alessio from Italy for creating this problem and sending it to me! A cyclist and a series of motorcycles are racing to the top of a long climb, and the cyclist doubles back. Given how many motorcycles passed the cyclist, can...
Curated Video
Can You Solve The Lying Fishermen Riddle? A Fantastic Algebra Puzzle
Thanks to Halvor Kjærås for creating this logic puzzle! Barney says he caught 5 fish, and Alfred says he caught 2. But each person fibs about numbers when spoken aloud. Can you figure out how many each person actually caught? My blog...
Curated Video
Can You Solve A Challenging Calculus Problem? The Circle Inscribed In A Parabola Puzzle
This is a challenging problem that ultimately works out pretty nicely. A circle with radius 1 is tangent to two points of the parabola y = x^2. What is the area between the circle and the parabola? Watch the video for a solution. Thanks...
Curated Video
Can You Solve The 3 Consecutive Numbers Puzzle?
I have found three consecutive integers such that their product is equal to their sum. What could my numbers be? Solve for all possibilities. Then watch the video for a solution. I thank Ken Edwards for creating the problem and Stephen...
Curated Video
Can You Solve The HARD Rectangle Ratio Puzzle? A SURPRISING Appearance Of Pi (π)
Start with a unit square (a rectangle with both sides equal to 1, call it R1). Attach a rectangle of area 1 to its right side, then attach a rectangle of area 1 to its top. The border of this new shape is another rectangle, call it R2....
Curated Video
Can You Solve The Magical Pond Puzzle?
(Same video with music: https://youtu.be/nF-Gpk0ZpRk) You visit a shrine that has 3 temples. Before each temple, you have to swim in a magical pond. Your path is pond-temple1-pond-temple2-pond-temple 3. Each time you swim, the pond...
Curated Video
Counter-Intuitive Probability: Can You Solve The Pair Of Aces Riddle?
A deck has 4 cards: the ace of spades, ace of clubs, 2 of spades, and the 2 of clubs. You draw 2 cards. What is the probability you drew 2 aces, if there is at least one ace? What is the probability if one of the cards is the ace of...
Curated Video
Counter-Intuitive Probability: The Snake Eyes Riddle
You close your eyes and roll a pair of dice. The casino dealer announces that at least one of the rolls is showing a 1.What is the probability that both dice are showing a 1? Watch the video for the solution. (Snake eyes is a term for...
Curated Video
Proving pi is irrational (using high school level calculus)
I did make one big typo/mistake in the video: at 3:40 I claimed that f(x) is a polynomial with integer coefficients. I meant to write n!f(x) is a polynomial with integer coefficients. Commenter ffggddss also pointed out some other...
Brian McLogan
Area of Inscribed Equilateral Triangle of Circle | Can You Solve?
Area of Inscribed Equilateral Triangle of Circle | Can You Solve?