by Ariel Marcy, 13 September 2023 | 6 comments

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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by Ariel Marcy, 30 August 2023 | 2 comments

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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by Ariel Marcy, 10 August 2023 | 4 comments

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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by Ariel Marcy, 26 July 2023 | 0 comments

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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by Ariel Marcy, 13 July 2023 | 1 comments

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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by Ariel Marcy, 29 June 2023 | 2 comments

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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by Ariel Marcy, 22 June 2023 | 0 comments

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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by David Shaw, 8 June 2023 | 2 comments

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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by Ariel Marcy, 24 May 2023 | 0 comments

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

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by Chenxin Tu, 10 May 2023 | 0 comments

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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