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Red and black brainteaser Brainteaser

by David, 12 June 2019 | 12 comments

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I have four playing cards: two of them are black and two are red. I turn them face down so you can’t see the colours, and shuffle them so you don’t know which is which. If you pick two of these cards at random, are they more likely to be the same colour or different…

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Taping tarps brainteaser Brainteaser

by David, 29 May 2019 | 3 comments

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Gerri has two identical square tarpaulins. Unfortunately, these tarps aren’t quite big enough to cover the brand new spa bath. So Gerri’s decided to cut the tarps and tape them together to make a bigger tarp. They want their final tarp to be a square, and they want it to be as big as possible….

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Sibling survey Brainteaser

by David, 15 May 2019 | 3 comments

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Emily has twice as many brothers as she has sisters. Her brother Bill has one more sister than he has brothers. How many boys and girls are in Emily and Bill’s family?

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The triple bounce Brainteaser

by David, 1 May 2019 | 4 comments

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I’m thinking of a two digit number. If you add the digits together and then multiply by three, you get the number back again! What number am I thinking of?

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The big triangle brainteaser Brainteaser

by David, 17 April 2019 | 4 comments

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At Three Peaks School, they’re planning to build a gigantic triangle. The sides have just arrived, on the back of some truly ridiculous trucks, and with police escort. The longest side is 42 metres long, with the other two sides measuring 25 and 16 metres respectively. Can you work out the area of the triangle…

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Blue eyed cows brainteaser Brainteaser

by David, 3 April 2019 | 1 comments

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Imagine a place called Occhiblu station, where they’re trying to breed cows with blue eyes. They have 100 cows on the station, and some of them have one blue eye. Of the rest of the cows, half have two blue eyes. Recently, one of the farmhands noticed that blue eyes are sensitive to light, so…

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Checking the clock brainteaser Brainteaser

by David, 20 March 2019 | 6 comments

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Terry is inspecting a huge clock. It’s 2:12 and they just finished examining the big hand. They need to check the little hand next, but they want it pointing in exactly the same direction that the big hand is pointing now. How long will they need to wait until the little hand is pointing that…

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Mathematical pizza party Brainteaser

by David, 6 March 2019 | 0 comments

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Four mathematicians – Annie, Beth, Carol and Donna – have a fun tradition. Every Friday, they order a pizza. But before they can eat, they must each solve a puzzle.

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No zeros Brainteaser

by David, 20 February 2019 | 2 comments

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Which two whole numbers – without any zeros – multiply together to make 1 000 000?

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Curious times Brainteaser

by David, 7 February 2019 | 7 comments

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Maryam had been practising the times tables really hard, so she was on the alert for interesting patterns. On her dad’s birthday she noticed something special. “You’re four times older than me, Dad,” she exclaimed. Four years later, she was counting the candles on her Dad’s birthday cake when she realised something mathematical. “You’re three…

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