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. If she tells him that the sums are 7, 12, and 13, can Jack recreate the secret numbers?
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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
Difficulty: Fun Catalina went on a game show and won their biggest prize! Catalina loves a good adventure, so she spent 3/4 of her prize money on a trip into space. She then spent 2/3 of her remaining money on training to climb Mount Everest. Finally, she donated the last remaining $100,000 to wildlife conservation. […]
By Ariel Marcy, 10 January 2024
Holly loves drawing with coloured pencils and her favourite colours have been sharpened a lot. She realises that her most favourite colour, rose, is exactly 3 centimetres long. She measures her other pencils and discovers that the teal pencil is exactly 4 centimetres, and the almond pencil is exactly 6 centimetres (cm). 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.
By Ariel Marcy, 6 December 2023
Can you find a different set of 5 positive whole numbers with the same stats?
By Ariel Marcy, 22 November 2023
Here’s a fun paper toy that can help you pick a future job. Have a go with our STEM career chatterbox! There are no wrong answers, only positive role models.
By Ariel Marcy, 14 November 2023
Difficulty: Fun Ellen has a set of 6 weights that come in pairs. One pair is a magical set of negative weights (think helium balloons that take weight away). 2 of the weights are 1 kilogram each, 2 of the weights are 5 kilograms each, and the 2 magical weights are -3 kilograms each. Ellen […]
By Ariel Marcy, 6 November 2023
Difficulty: Fun Triangular numbers are numbers that can be formed into a triangle. For example, 3 is a triangular number with 2 dots on the bottom row and 1 dot on top row forming an equilateral triangle of 3 dots. 6 is the next triangular number with 3 dots on the bottom, 2 dots in […]
By Ariel Marcy, 23 October 2023
Difficulty: Tricky Anas is making a map of his friend group. In his map, each circle is a person. A line joins 2 circles if and only if those 2 people are friends. Using the clues below, can you figure out who goes where on the map? 1. Anas has 3 friends: Ruth, Mitra, and […]
12 months, 8 issues
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Perfect for ages 8 – 14
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