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?
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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, 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, 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, […]
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