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Prime number brainteaser Brainteaser

by David Shaw, 9 March 2023 | 1 comments

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Difficulty: Extreme 123,456,789 is not a prime number. Is it possible to reorder its digits to give a prime number?

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George’s lollies brainteaser Brainteaser

by David Shaw, 23 February 2023 | 2 comments

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Difficulty: Extreme! George bought a bag of 70 lollies on Monday. He didn’t eat many on Monday, but he really liked the flavour. Every day after that he ate three more lollies than he had the previous day. The next Monday, George was about to eat his first lolly for the day and noticed the…

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Australian coins brainteaser Brainteaser

by David Shaw, 15 February 2023 | 0 comments

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Difficulty: Fun Jane has some Australian silver coins in her pocket. When buying an apple, she realises she has more than $1 in silver coins, but can’t make exactly $1 with her coins. How is this possible? (Silver Australian coins come in 5c, 10c, 20c, and 50c.)

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Pool leak brainteaser Brainteaser

by David Shaw, 5 January 2023 | 0 comments

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Difficulty: Fun While Eddie is away on holidays his swimming pool has a leak. Each day it loses half the water still in the pool. Normally, it’s 1.6 metres deep, but when Eddie gets home there is only 10 centimetres of water in the bottom. How long has the pool been leaking?

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Santa scramble Brainteaser

by David Shaw, 5 December 2022 | 1 comments

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Santa sent out 2 sleigh teams. One goes east, and the other goes west, until they meet. how far away from home are they when they meet?

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Chocolate choice brainteaser Brainteaser

by Fiona Midson, 24 November 2022 | 0 comments

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Three new chocolate brands are being released: Jupiter, Astro, and Celeste. can you use up all the ingredients to make these bars?

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Alien academy brainteaser Brainteaser

by David Shaw, 9 November 2022 | 0 comments

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Difficulty: Tricky A new class of aliens is due to start at Alien Academy. The teachers need to know the age of each alien, but can’t contact them. Luckily, they have a few clues to help them. There are five aliens (Filp, Agg, Nim, Phod, and Mex) and each alien is a different age (7,…

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Who lives next door? A brainteaser Brainteaser

by David Shaw, 19 October 2022 | 1 comments

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Difficulty: Tricky There are 4 houses that stand in a row. One family lives in each house. The O’Connells live next door to the Taos, but they don’t live next door to the Sosas. The Prasads don’t live next door to the Sosas. Who lives next door to the Prasads?

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Growing dough brainteaser Brainteaser

by David Shaw, 6 October 2022 | 2 comments

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Difficulty: Extreme! Nguyệt keeps a bread dough in her fridge. She tends to it so that every day it doubles in size, and then every morning, she cuts off enough dough to make one loaf of bread for her breakfast.

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My favourite book brainteaser Brainteaser

by David Shaw, 23 September 2022 | 0 comments

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Difficulty: Fun On my bookshelf, my favourite book is the third from the left, and it’s the seventh from the right. How many books are there on that shelf?

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