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, 6 December 2023
Can you find a different set of 5 positive whole numbers with the same stats?
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 […]
By Ariel Marcy, 4 October 2023
Difficulty: Tricky Ahmad’s computer scientist mother gives him a binary stopwatch that counts minutes using only 1’s and 0’s – just like a computer! The binary stopwatch has 6 placeholders where the 1’s and 0’s appear. When the binary stopwatch is reset, all the placeholders are zeros. Ahmad finds a regular stopwatch, resets both stopwatches, […]
By Ariel Marcy, 27 September 2023
Difficulty: Tricky You have 2 glasses, each filled with 100 millilitres (ml) of soda. One contains cola and one contains orange soda. First, you take a spoonful of cola and mix it into the orange soda. Next, you take an equal spoonful of the orange-cola mixture and put it into the glass of cola. Which […]
By Ariel Marcy, 13 September 2023
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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