Curated Video
Can You Solve The Marriage Logic Problem? 80% Fail
Surveys have found 80 percent get this logic problem wrong. Alice is looking at Bob, and Bob is looking at Charlie. Alice is married; Charlie is not. Is a married person looking at an unmarried person? Answer choices are A) Yes, B) No,...
Curated Video
9 - 3 ÷ 1/3 + 1 = ? The Correct Answer (Viral Problem In Japan)
What is 9 - 3 ÷ 1/3 + 1 = ? This problem went viral in Japan after a study found 60 percent of 20 somethings could get the correct answer, down from a rate of 90 percent in the 1980s. I explain a common mistake and how to get the correct...
Curated Video
The Prisoners Dilemma - The Most Famous Problem in Game Theory
The Prisoner's Dilemma is the most famous problem in game theory, as it shows that individuals who make rational decisions might end up in an outcome that's worse for everyone in the group. In other words, individual rationality does not...
Curated Video
Introduction to Factor Theorem and Factoring Polynomials
The video is a lecture presentation about the factor and remainder theorems in mathematics. The presenter explains how to use the factor theorem to find factors and remainders of polynomials by substituting specific values and also...
KnowMo
Problem Style Questions for Sequences
The video is a lecture on solving problems related to sequences. The lecturer explains that this topic is a favorite for examiners because they can ask various questions that require logical thinking beyond applying class processes. The...
Crash Course
P-Value Problems - Crash Course Statistics
Last week we introduced p-values as a way to set a predetermined cutoff when testing if something seems unusual enough to reject our null hypothesis - that they are the same. But today we’re going to discuss some problems with the logic...
Curated Video
HOW SMART ARE YOU? 80% FAIL The Dance Club Line Logic Riddle
There is a long single-file line outside of a dance club. The first person in line is unmarried, and the last person in line is married. Each person in line only looks at the person in front of them. Is a married person looking at an...
Curated Video
The HARDEST Logic Puzzle Ever (Simpler Version): Two Doors To Freedom Riddle
An evil warden holds you prisoner, but offers you a chance to escape. There are 3 doors A, B, and C. Two of the doors lead to freedom and the third door leads to lifetime imprisonment, but you do not which door is what type. You are...
Curated Video
The REAL Answer To The Viral Chinese Math Problem "How Old Is The Captain?"
Media outlets around the world went crazy over a 5th grade math exam question in China. But they all missed the real story! The problem actually dates back to French researchers in 1979. In this video I present the real story to the...
Curated Video
"UNSOLVABLE" Logic Puzzle: What Are Their Ages?
This is one of those brain teasers that sounds like it's impossible to solve but you can work through it (like the logic puzzle of Cheryl's birthday). A mathematician tells a census taker he has 3 children. The product of their ages is...
Curated Video
Can You Solve The Rabbit Race Logic Puzzle?
How can 10 rabbits plan races so each rabbit "beats" every other rabbit in some race? What if there are n rabbits? My blog post for this video: https://wp.me/p6aMk-55O Source I received this problem by email from Stephan who translated...
Curated Video
Can You Solve The Mind-Twisting Logical List Riddle?
In a list of 10 statements, the nth statement says there are exactly n false items in the list. Which of the statements, if any, are false? What if the nth statement says there are "at least" n false items? The video presents a solution...
Curated Video
When Is Cheryl's Birthday? Answer To Viral Math Puzzle
This problem went viral after it appeared on a Math Olympiad test for talented students in Singapore. It's not a trick question! Here's the problem, which I have very slightly re-worded for clarity. Blog post (detailed text explanation):...
Curated Video
"Impossible" Logic Puzzle - How Many Liars Are At The Party?
A party has 100 people who are either liars are truth tellers. Liars always lie and truth tellers always say the truth. After the party you ask each person, "How many truth tellers did you shake hands with?" Each person gives a different...
Curated Video
Game Theory: Why Cherry Picking Should Not Work In The NBA
Could cherry-picking work in the NBA? Perhaps it could work in actual play. But in theory, as I suggest using game theory, there are logical reasons why cherry-picking should not work as a dedicated strategy. Sacramento Kings "Owner...
Curated Video
MIND-BENDING LOGIC PUZZLE - The Self-Counting Sentence
"In this sentence, the number of occurrences of the digit 0 is __, of the digit 1 is __, of the digit 2 is __, of the digit 3 is __, of the digit 4 is __, of the digit 5 is __, of the digit 6 is __, of the digit 7 is __, of the digit 8...
Curated Video
The Four Color Codes Logic Riddle
Mr. White, Mr. Blue, Mr. Brown and Mr. Pink are wearing shirts that match their names, but no one is wearing the same color shirt as their name. They exchange a few words that give hints about what color shirt each person is wearing. Can...
Curated Video
Two Grade School Math Questions Stumping Adults Worldwide Right Now
Media outlets around the world are reporting on these math problems that have "flummoxed" everyone. As these got so much attention, I wanted to share some of the headlines and give a small discussion about what I think is the real lesson...
Curated Video
Can You Solve The "IMPOSSIBLE" Handshake Logic Puzzle?
Mr. Lars and his wife Mrs. Lars went to a meetup and met 4 other married couples. Some people shook hands with each other, but no person shook hands with his or her spouse, and no person shook his or her own hand. Mr. Lars then asked...
Curated Video
HARD Logic Puzzle - The Seemingly Impossible Counterfeit Coin Problem
An evil warden holds you prisoner, but offers you a chance to earn your freedom. You are given 101 coins, of which 51 are genuine and 50 are counterfeit. Each genuine coin is identical. And each counterfeit coin is identical to a genuine...
Curated Video
HARD Logic Puzzle: How Can Spies Share Secrets Efficiently?
After a successful mission, each of N spies obtains a unique secret. By protocol, the spies share secrets by a series of phone calls between 2 spies at a time. During a call, a spy can share all the secrets the knows, including secrets...
Curated Video
Teresas Daughter Is My Daughter's Mother - Viral Facebook Logic Puzzle
This problem already has over 175,000 shares on Facebook. Can you solve it? "If Teresa's daughter is my daughter's mother, then what is my relationship to Teresa?" a. her grandmother b. her mother c. her daughter d. her granddaughter e....
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
Internet Stumped By This Singapore Math Problem
It's not the famous Cheryl's birthday problem...According to Mothership, this math problem is causing a lot of confusion: "There are 37 students in a class. How many students, at the least, are born in the same month?" Now I think the...