By Ariel Marcy, 29 May 2024
Anamaria and Chen are two friends who toured a magical chocolate factory! They both get enormous amounts of chocolate and they want to share it evenly between them. Anamaria gets 1,574,936 squares of chocolate and Chen gets 3,569,321 squares of chocolate. Without using a calculator, can you tell if it is possible for them to share the chocolate between them without breaking any squares?
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By Ariel Marcy, 21 May 2024
Difficulty: Tricky Jack is making a quilt from only square patches of fabric. For every 4 patches he sews together, 1 patch is blue and 3 patches are red. Once they are added to the quilt, all of the patches are 5 cm in width and length. Jack wants to make a quilt that is […]
By Ariel Marcy, 24 April 2024
Miguel hopes to become a magnificent mathematical magician. For his first trick he wants to present a standard 52-card deck and dramatically draw a face card (Jack, Queen or King). If the deck is randomly shuffled, what is the probability that Miguel will draw a face card on the first try?
By David Shaw, 10 April 2024
Sienna’s teacher is writing up a wicked problem. First, the teacher writes all the numbers from 1 to 99 and then erases 10, 20, and all the other numbers that end in 0. “Listen up! Multiply all these numbers. Tell me the last digit and I’ll give you full marks on your next assignment.”
By Ariel Marcy, 21 March 2024
Flora likes to run up stairs as fast as she can! Sometimes she lands on every stair and sometimes she skips a stair, taking two in one stride. This gets her thinking: how many different ways can she run up a staircase?
By Ariel Marcy, 12 March 2024
Lavonne is testing a secret code with her friend Jack. First, she picks 3 different secret numbers between 1 and 9. Then she finds the sum of each pair of numbers. Lavonne wants to know if Jack can figure out the original secret numbers just from the sums?
By Ariel Marcy, 26 February 2024
Farmer Wallace packages his eggs in cartons that hold a dozen eggs. In March, he sells 5 standard orders of eggs to the local grocery store. Each standard order consists of 4 grosses of eggs. A gross is 144 eggs. How many cartons of eggs did Farmer Wallace sell?
By Ariel Marcy, 13 February 2024
Catalina won a game show prize! She spent 3/4 of it on a trip into space. She spent 2/3 of her remaining money climbing Mount Everest. Finally, she donated the last $100,000 to wildlife. How much did she win?
By Ariel Marcy, 10 January 2024
Holly loves drawing and her favourite colours have been sharpened a lot. Her most favourite colour, rose, is exactly 3cm long. She discovers that the teal pencil is exactly 4cm, and the almond pencil is exactly 6cm. What lengths from 1-10 cm can Holly make with her pencils?
By Ariel Marcy, 14 December 2023
In 2023, Double Helix readers busted a bunch of brainteasers! Here are the tippy-top, most popular puzzles of the year.
12 months, 8 issues
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Perfect for ages 8 – 14
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