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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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.
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?
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.
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.
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?
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.”
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. […]
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 […]
By David Shaw, 30 September 2021
Difficulty: Tricky Last week, there was an earthquake near Mount Buller in Victoria. The shaking reached central Melbourne around 9:16:30, and Canberra at 9:17:30. It’s 120 kilometres from the earthquake epicentre to central Melbourne, and 360 kilometres from the epicentre to Canberra. From the epicentre to Sydney, it’s 600 kilometres. What time did the shaking […]
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