# Blog

## Oranges brainteaser

By David Shaw, 24 March 2022

Difficulty: Extreme! These 2 brothers sold oranges for a living. On Monday: Josh priced his oranges at 2 for $3. He sold 30 oranges for $45. Zach priced his oranges at 3 for $4. He sold 30 oranges for $40. On Tuesday, they combined their prices, and sold their oranges in groups of (2 + […]

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## Jasper’s shapes brainteaser

By David Shaw, 9 March 2022

Difficulty: Tricky Jasper had a regular (sides and angles all the same) hexagon with 10-centimetre sides, and 3 regular triangles with 10-centimetre sides. He put the side of a triangle against every second side of the hexagon. How many sides did this final shape have?

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## School uniform brainteaser

By David Shaw, 23 February 2022

Difficulty: Tricky Keira is getting ready for school: She has 3 different shirts – one black, one white and one red. She has 3 different pairs of pants – one black, one white and one red. She has 3 different pairs of shoes – one black, one white and one red.

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## Flight tracker brainteaser

By David Shaw, 9 February 2022

Difficulty: Tricky Last week I flew from Canberra to Brisbane. The plane took off at 2.00 pm, flew 1,800 kilometres at 900 kilometres per hour, and landed at 3.00pm. On the way home from Brisbane, the plane took off at 8.00 pm. Assuming it flew at the same speed, when did it land in Canberra?

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## Dart maths brainteaser

By David Shaw, 19 January 2022

Difficulty: Tricky At the 2022 World Darts Championship, William Borland beat Bradley Brooks with a perfect final leg, scoring precisely 501 points.

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## Guarding the castle brainteaser

By David Shaw, 3 December 2021

Difficulty: Tricky There are 32 soldiers guarding a square castle. The castle has 8 towers – one in each corner of the square, and one in the middle of each side. The soldiers want to make sure all the walls are guarded.

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## A crowded bus brainteaser

By David Shaw, 24 November 2021

Difficulty: Fun The number 39 bus was packed as it pulled into the interchange. Then 37 people got off, and another 14 got on. As the bus left the interchange, there were 37 people on board. How many people were on the bus as it pulled into the interchange?

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## Joining five dots brainteaser

By David Shaw, 10 November 2021

Difficulty: Extreme! Ziqi’s teacher loved puzzles, and posed a difficult challenge: “Draw five dots on a piece of paper. Now, connect each dot to every other dot. Each pair of dots needs to be connected by a line, which doesn’t need to be straight.”

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## Coloured cups brainteaser

By David Shaw, 20 October 2021

Difficulty: Tricky Scarlett, Azure and Jett were drinking tea together. There was one scarlet red teacup, one azure blue mug and a jet-black tea glass. None of them had a cup that was the same colour as their own name. After a while, Scarlett offered to get the person with the black glass another drink. […]

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## Reshuffling cars brainteaser

By David Shaw, 13 October 2021

Difficulty: Extreme! Terri runs a car showroom. It has 3 roads to park cars on, which all meet in the middle of the showroom. Terri can fit 3 cars on each road. If she tries to park a fourth, it blocks the intersection in the middle. At the moment, there are 2 Audis on one […]

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