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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...
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Sets: Infinity
Discover why infinity puzzled the Greeks, and why this led to the discovery that there is more than one type of infinity. Maths - Algebra A Twig Math Film. Reinforce and extend the learning required by the curriculum. Twig’s context...
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Solve If You Are A Genius (From 1869). Harvard Admissions Question Algebra Problem
The Harvard admissions exam in 1869 included this algebra problem: "A man bought a watch, a chain, and a locket for $216. The watch and locket together cost three times as much as the chain, and the chain and locket together cost half as...
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Multiply Numbers And Algebra Equations By Drawing Lines
Some people say this is "how the Japanese multiply." Others say this is "Vedic Math." I'm not sure of the origin, but this is a visual way to multiply two numbers and it does work. The video also shows how to use the same method to...
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MATHS PROBLEM STUMPING THE INTERNET - Bananas, Clock, Hexagon Algebra Problem Solved
This emoji math puzzle is going viral and being shared with claims like "only a genius can solve it" or "99 percent fail." In this video I present what many people believe to be the correct answer. My blog post for this video:...
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Homework In China Stumps Adults - The Flower Algebra Problem
This emoji math problem is said to come from a test given to a Chinese kindergarten class (5 year olds). It was posted online and caused a lot of debate as adults were stumped about the correct answer, some saying it is impossible. Can...
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Can You Solve The Cat, Fish, And Bird Riddle? This Algebra Problem Tricks Many
A child spent $100.00 to get 100 toy animals. The child bought at least one cat, one fish, and one bird, and did not buy any other toys. If a cat costs $10.00, a fish costs $3.00, and a bird costs $0.50, how many of each toy did the...
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Impossible Algebra Problem
This problem is making the rounds. Can you place numbers in the four boxes so all the equations are true? Blog post (text/image explanation): http://wp.me/p6aMk-4up If you like my videos, you can support me at Patreon:...
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"Only A Genius Can Solve" Viral Math Problem - The Horse, Horseshoe, Boots Problem
A lot of people are arguing over the correct answer to this emoji math algebra problem involving horses, horseshoes, and boots. A Facebook post with this problem has over 500,000 comments. Can you figure it out? In this video I explain...
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Can You Solve An MIT Test Question (in 1869)? The Order Of Operations
The MIT entrance exam in 1869 had a problem about the order of operations. As these types of math questions often go viral on Facebook and Twitter with heated arguments, it would be interesting to see if students today could solve this...
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MIND-BLOWING MATH DISCOVERY - Multiply Numbers By Lines Rotation Geometry
Since 2007, millions of people have watched videos on "how the Japanese multiply," also known as "Chinese stick multiplication" or "Vedic Math." With millions of people watching these videos, you would expect everything is known about...
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Viral Math Problem "Stumping The Internet" - Coconut Plus Apple Plus Banana
This emoji math problem has over 2 million comments on Facebook and is getting coverage in mainstream media and blogs. Can you figure out this Facebook fruit algebra puzzle involving apples, bananas, and coconuts? The video presents what...
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Which Is Faster: Run Half The Distance Or Half The Time?
Thanks to Muztoba Ali in Bangladesh for this problem! Two brothers, A and B, have the exact same walking speed and the exact same running speed. One day they started the same trip to the same place. Brother A walked for half of the...
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"Prove" 3 = 0. Can You Spot The Mistake?
Thanks to Lucas from Brazil who sent this problem! This is a proof that 3 = 0 using sneaky algebra that I had never seen before (this is a sneaky mistake, not a simple divide by 0 fallacy). Every step seems correct, but the conclusion is...
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Most US College Students Cannot Solve This Basic Math Problem. The Working Together Riddle
To complete a job, it takes: Alice and Bob 2 hours, Alice and Charlie 3 hours, and Bob and Charlie 4 hours. How long will the job take if all 3 work together? Many, many US college students set up the equations incorrectly and get the...
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Can You Solve The Number Of Children Riddle?
Many people make mistakes in this seemingly routine algebra problem. The average age of a family (two parents and their children) is 20. If we exclude one parent, who is 40, the average age drops to 15. How many children are in the...
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Can You Solve This Crazy Equation? Ramanujan's Radical Brain Teaser
In 1911, Srinivasa Ramanujan posed this problem involving an infinite nested radical (a never-ending expression that has square roots inside of square roots). Can you figure out how to simplify the equation? The video presents an...
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How Many Triangles Are There? Learn The Formula For Any Size!
How many triangles are formed in a grid of equilateral triangles with N triangles in its base? The video shows a pattern in the case of n=4 and presents a formula for the general case. Blog post (text explanation): http://wp.me/p6aMk-4sO...
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The Quadratic Formula - Why Do We Complete The Square? INTUITIVE PROOF
The quadratic formula is really useful, but its derivation is confusing to many. Like what is the point of "completing the square" anyway? In this video, I show how "completing the square" has a geometric interpretation--you are actually...
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Smartphone App Solves Common Core Test Problems
PhotoMath is a pretty neat app that can solve math problems instantly. Here is the app solving some sample Common Core test questions. Links to the free app and more below... PhotoMath App (Currently free on iPhones, Android, Windows,...
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HOLIDAY RIDDLE - In The "12 Days Of Christmas," How Many Total Gifts Are Given?
You may remember the song "12 Days of Christmas" in which each day you get N gifts, plus all the gifts from the preceding days. How many gifts are given in total? What's a general formula? Algebraic proof...
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How Crossed Ladders And Working Together Problems Are Related - The Harmonic Mean
Problem 1: Two ladders are criss-crossed against walls of height 3 and 5. At what height do they intersect? Problem 2: I take 3 hours to complete a job, and you take 5 hours to do the same job. How long does it take if we work together?...
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Why It Works: Quickly Square a Number Ending in 5
Sorry I made a major algebra mistake in the video! The correct formula is 100x^2 + 100x + 25 which then equals 100(x(x+1)) + 25. Video explaining trick: http://youtu.be/oV7Kxm3Zr_c Vedic Math Method Ekadhikena Purvena "By one more than...
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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...