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Post Type: Brainteaser

4 equal rectangles Brainteaser

by Ariel Marcy, 13 September 2023 | 6 comments

Rectangle with H shaped lines inside creating four new rectangles.

Difficulty: Fun The big rectangle below is made from 4 small rectangles. All the small rectangles are equal, meaning that they have the same size and shape. If the small rectangle’s short side is 8 centimetres, what is the length (long side) of the bigger rectangle?

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An odd observation Brainteaser

by Ariel Marcy, 30 August 2023 | 2 comments

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Difficulty: Tricky Alex is playing a dice game with 2 standard 6-sided dice, one red and one blue. Each die has faces numbered from 1 to 6. Alex rolls both dice and adds up the numbers on the top faces. After a while, Alex notices that the sums are always between 2 and 12 and…

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Divide by this Brainteaser

by Ariel Marcy, 10 August 2023 | 4 comments

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Difficulty: Extreme A teacher wrote a whole number on the whiteboard and asked her students to say what numbers it could divide by. The 1st student said, “the number is divisible by 1.” The 2nd student said, “the number is divisible by 2.” The 3rd student said, “the number is divisible by 3.” And this…

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A cup conundrum Brainteaser

by Ariel Marcy, 26 July 2023 | 0 comments

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Difficulty: Tricky Fernando has 3 water-tight containers that measure 3 cups, 9 cups, and 20 cups (for brevity, these are referred to as C3, C9, and C20, respectively). The containers have no markings to indicate other volumes, so there’s no way to know when a container is, say, half full. The containers have nice spouts,…

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Welcome to the dog show Brainteaser

by Ariel Marcy, 13 July 2023 | 1 comments

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Difficulty: Fun There are 50 total dogs signed up for a dog show. There are 30 more small dogs than large dogs. How many small dogs have signed up to compete in the show?

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Out Of This World Brainteaser

by Ariel Marcy, 29 June 2023 | 2 comments

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Difficulty: Fun Mariana the astronaut weighs 51 kilograms on Earth and 8.5 kilograms on the Moon. Mariana is training Javier to go to the Moon. If he weighs 78 kilograms on Earth, how much will he weigh on the Moon?

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Great to Meet You! brainteaser Brainteaser

by Ariel Marcy, 22 June 2023 | 0 comments

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Difficulty: Tricky You’ve just joined a new Scouts group! You meet 4 other new people, and everyone is going around giving handshakes. If everyone shakes hands with everyone else exactly once, how many handshakes will there be in total? (Remember you can’t shake hands with yourself.)

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Regeneration brainteaser Brainteaser

by David Shaw, 8 June 2023 | 2 comments

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A sea sponge gets attacked by a shark and is ripped into 100 pieces. Luckily, sea sponges can join back together after they’ve been broken apart. Some pieces form into groups of 7, and the rest form into groups of 29. In the end, there are no pieces left. How many sponges do we end…

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Sequence This Brainteaser

by Ariel Marcy, 24 May 2023 | 0 comments

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Difficulty: Tricky Consider the following sequence of numbers. What number comes next? 1, 1, 2, 3, 5, 8, 13…

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Sleepy time brainteaser Brainteaser

by Chenxin Tu, 10 May 2023 | 0 comments

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Lisa had a difficult time falling asleep on Wednesday night, so she began counting sheep. How many sheep did she count?

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