# Blog

## A maths prize for packing balls

By David Shaw, 21 July 2022

Have you ever struggled to pack balls back into your toy box? The Fields Medal, one of the most famous prizes in mathematics, was recently announced. One of this year’s winners, Ukrainian mathematician Maryna Viazovska, is an expert in packing balls in boxes. But there’s a catch! Her findings work in 8 dimensions (D) and beyond.

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## Try a tangram

By David Shaw, 20 July 2022

This traditional Chinese puzzle, known as a tangram, reveals some surprising properties of squares!

## Five makes 80 brainteaser

By David Shaw, 13 July 2022

Can you find 5 consecutive (counting upwards) numbers that add up to 80?

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## Two trains brainteaser

By David Shaw, 29 June 2022

Difficulty: Fun A fast passenger train leaves Sydney Central station, headed for Broken Hill. At the same time, a slow freight train, moving at only half the speed of the passenger train, leaves Broken Hill station, headed for Sydney Central. When they meet, which train is closer to Sydney?

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## Selling random numbers

By David Shaw, 23 June 2022

It sounds like a perfect way to make money – scientists from The Australian National University (ANU) are now selling random numbers over the internet! But before you start your own business writing whatever number pops into your head, there’s something special about these numbers.

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## Too many elevens brainteaser

By David Shaw, 16 June 2022

How many 1s does it take to write out the number eleven thousand, eleven hundred and eleven?

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## Paying the miller brainteaser

By David Shaw, 2 June 2022

A farmer goes to the local mill to get some wheat ground into flour. The miller doesn’t ask for money – instead, they take one tenth of the wheat as payment. If the farmer wants 100 kilograms (kg) of flour at the end, how much wheat should they bring?

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## Soma cube

By David Shaw, 24 May 2022

The soma cube is a tricky puzzle! First, you’ll glue some cubes together into strange shapes. Then see if you can get those shapes to come together!

## Srinivasa’s street brainteaser

By David Shaw, 18 May 2022

Difficulty: Extreme! Srinivasa lives in a house on a short street, with houses on one side. The houses are numbered 1, 2, 3 and so on. He was practicing his addition when he noticed something strange.

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## Solo noughts and crosses brainteaser

By David Shaw, 5 May 2022

Difficulty: Tricky Mabel wanted to play noughts (O) and crosses (X), but she didn’t have anyone to play with. So she just took one go after another. Somehow, Mabel put Xs in 6 of the 9 squares without making a line of 3 Xs. Can you draw the board and work out which squares have […]

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