Curated Video
Can You Solve The Knight On A Chessboard Riddle? Math Olympiad Problem
Alice and Bob are playing a game. Alice starts by placing a knight on the chessboard. Then they take turns moving the knight to a new square (standard chess rules apply: the knight moves in an "L" shape). The first player who cannot move...
Curated Video
Only 25% Could Solve This 8th Grade Geometry Problem
What is angle A in the star-shaped figure? This problem appeared on the 1999 AMC 8 test (intended for 8th grade students in the US). Approximately 75% of test-takers did not mark the correct response. Can you figure it out? Watch the...
Curated Video
Evil Geometry Question - The 6 Rectangles Puzzle
What is the perimeter of the shape consisting of 6 rectangles, if a single rectangle has a perimeter of 222? It seems like there is not enough information to solve the problem. But there is! The video illustrates 2 different methods to...
Curated Video
Can You Solve This Grade 12 Geometry Problem From Australia? The Marshmallow Chocolate Puzzle
A marshmallow has the shape of a cylinder with diameter 5 and height 3. A dessert is made with 24 marshmallows: there are two stacked layers of marshmallows, and each layer has 3 rows of 4 marshmallows. The gaps between the marshmallows...
Curated Video
Can You Solve The Shape-Shifting Triangle?
This delightful problem comes from a German math competition. What's the perimeter of the triangle CDE? You have 3 minutes to solve this problem. Watch the video for a solution, and to see the shape-shifting triangle hidden in this...
Curated Video
Can You Divide The Shape Into 4 Equal Parts?
Here's the solution: https://www.youtube.com/watch?v=_JetDMSfWtg If you like my videos, you can support me at Patreon: http://www.patreon.com/mindyourdecisions Connect on social media. I update each site when I have a new video or blog...
Curated Video
Baseball's Home Plate Is IMPOSSIBLE Mathematically
Home base is defined by a geometric construction. Take a square whose side is 17" and then remove two corners. The adjacent sides are 8.5", and the two remaining sides are 12" and meet at a right angle. The only problem: this is an...
Curated Video
Can You Solve The Tetris Puzzle?
In the game of Tetris, there are 7 pieces, each made up of 4 square units. (The shapes are called "tetrominoes" in mathematical literature.) Here's the puzzle. Can you use one of each piece to form a 7x4 rectangle? If so, find a way. If...
Curated Video
Only 7% Could Solve This 8th Grade Problem
Which figures can you form from the two shapes A and B? This is a sample question from the 2017 NAEP for 8th grade US students. Be sure to select all of the correct choices! It's tricky, only 7 percent found all of the correct answers....
Kids Academy
Worksheets: Preschool & Kindergarten Learning - Virtual Learning & Real-Life Practice
Our new app Worksheets: Preschool & Kindergarten Learning already available on the App Store: https://smart.link/59833db06a6b8 and Google Play: https://smart.link/597210af6eb83 Subscribe to our channel: https://goo.gl/iG2Bdr Trace and...
Curated Video
Lune Of Hippocrates - Famous Ancient Math Problem
Hippocrates of Chios solved this, nearly 100 years before Euclid even wrote The Elements, and before we knew the exact formula for the area of a circle. This is said to be the first precise mathematical of the area between two curved...
Curated Video
Solved On TV In Only 10 Seconds! Trick To Count Rectangles Quickly
Can you count the number of rectangles in the grid? How about in the L-shaped grid? These problems appeared on the TV show Superhuman hosted by Kal Penn (Kalpen Modi). The contestant Summer gave the correct answer to each challenge in...
Curated Video
What's The Best Soup Can Size? Solved With Calculus!
A cylindrical can with volume V can be made in different ways. The cylinder can be wide and short (large radius and small height), or it can be narrower and taller (small radius and larger height). Which shape uses the least material?...
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
Almost Everyone Got This Question Wrong. Can You Solve It?
A tetrahedron and a pyramid have edges of equal length. If they are glued together on a triangular face with the vertices aligned, how many faces will the new shape have? This question is trickier than it looks! It stumped the...
Curated Video
"98% Fail" - How Many Triangles Are There? Viral Bollywood Puzzle
This problem caught the attention of Bollywood celebs, including Sonam Kapoor, Aditi Rao Hydari, and Diana Penty, after fashion magazine editor Jitesh Pillai tweeted it. How many triangles are there? This is not just a simple test of...
Curated Video
Can You Solve The HARDEST Matchstick Puzzle? "Outside The Box" Thinking!
Can you use 6 matches to make 4 triangles of equal size and equal shape? This is harder than it sounds! Give it a try before watching the video for a solution. If you like my videos, you can support me at Patreon:...