By Ariel Marcy, 15 January 2025
Rita is making lamingtons for her birthday party and cuts them precisely into 5-centimetre cubes. While playing around with an antique balance scale, she discovers that one lamington is equal to 50 grams plus half a lamington. At her party, she eats one and a half lamingtons. How much did Rita’s dessert weigh?
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By David Shaw, 10 December 2024
Here are eight 8s, 8 8 8 8 8 8 8 8. Put some plus signs in there to make 1000.
By Ariel Marcy, 19 November 2024
Farmer Doolittle has a farm with just cows and chickens. The farmer counts up all the animals and discovers that there are 43 heads and 120 legs on the farm (not counting the farmers). How many cows live on farmer Doolittle’s farm?
By Evrim Yazgin, 31 October 2024
The biggest ever prime number has just been found and it’s absolutely massive. It’s a number with more than 41 million digits. That means, if you were to type it out in size 12 font, it would be more than 8,000km long! That’s about the distance from Melbourne to Tokyo.
By Ariel Marcy, 9 October 2024
Right before the bell rings, Jeri’s teacher throws up a problem on the board: “I’m thinking of a number. When I add its digits together and multiply by seven, I get the number I first thought of. The number is under 40.” Can you help Jeri find the number before class is dismissed?
By Ariel Marcy, 10 September 2024
A team of geologists are using the latest technology to drill into the Earth’s ocean floor and look at the rock underneath! They manage to drill a total of 1250 metres (based on a recent true story!). But the drilling gets harder the deeper they get.
By David Shaw, 29 August 2024
Eight people come together for a very important meeting. How many ways can just one person sit in the wrong chair?
By Ariel Marcy, 13 August 2024
In this puzzle, each Aussie animal stands for a number. Each animal represents the same number throughout the puzzle. Can you use the first three mathematical equations to figure out the answer to the last equation?
By Ariel Marcy, 30 July 2024
A team of engineers have invented a new, stretchy battery that is clear. Another team have invented a jelly-like battery that is rainbow coloured. Both teams want to compare how long their batteries last to a regular, silver AA battery.
By Ariel Marcy, 16 July 2024
Lavonne is a security guard who has to walk around the outside of an L-shaped building. She knows the length of the longest sides, 200 metres and 140 metres. She also knows the shape of the building and that each of the angles are 90 degrees. What is the building’s perimeter?
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