# Blog

## Brainteaser: Break the prime code

By Ariel Marcy, 5 November 2024

We’ve written a code using two different prime numbers less than 10. We then multiplied these two primes and used the resulting “code number” to shift the alphabet forward to new letters. Can you use the clues above to decode this message: DRO QYVN SC LEBSON SX DRO QKBNOX.

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## Biggest prime number found!

By Evrim Yazgin, 31 October 2024

The biggest ever prime number has just been found and it’s absolutely massive. It’s a number with more than 41 million digits. That means, if you were to type it out in size 12 font, it would be more than 8,000km long! That’s about the distance from Melbourne to Tokyo.

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## Brainteaser: Fairy bread

By Ariel Marcy, 23 October 2024

Rosario has a pink square of origami paper. She then folds one corner all the way to the square’s centre to make a new 5-sided shape. She discovers that the missing corner is exactly the same size as a piece of fairy bread! How many pieces of fairy bread would it take to cover the whole 5-sided shape?

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## Brainteaser: Beat the bell

By Ariel Marcy, 9 October 2024

Right before the bell rings, Jeri’s teacher throws up a problem on the board: “I’m thinking of a number. When I add its digits together and multiply by seven, I get the number I first thought of. The number is under 40.” Can you help Jeri find the number before class is dismissed?

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## Brainteaser: NASA spacecraft logic

By Ariel Marcy, 24 September 2024

Can you solve this grid-based logic puzzle about NASA? You are doing a science project about four of NASA’s spacecraft: Clipper, DAVINCI, Dragonfly and MAVEN. Each spacecraft will visit another planet in the solar system: Venus, Mars, Jupiter and Saturn. They also have different launch dates: 2013, 2024, 2028 and 2030.

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## Brainteaser: Drilling the distance

By Ariel Marcy, 10 September 2024

A team of geologists are using the latest technology to drill into the Earth’s ocean floor and look at the rock underneath! They manage to drill a total of 1250 metres (based on a recent true story!). But the drilling gets harder the deeper they get.

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## Wrong seat brainteaser

By David Shaw, 29 August 2024

Eight people come together for a very important meeting. How many ways can just one person sit in the wrong chair?

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## The shape of science – a quick quiz

By David Shaw, 20 August 2024

This quiz looks at some of the shapes found in maths and science. Give it a go and see how you shape up!

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## Brainteaser: Animal equations

By Ariel Marcy, 13 August 2024

In this puzzle, each Aussie animal stands for a number. Each animal represents the same number throughout the puzzle. Can you use the first three mathematical equations to figure out the answer to the last equation?

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## Brainteaser: Batteries

By Ariel Marcy, 30 July 2024

A team of engineers have invented a new, stretchy battery that is clear. Another team have invented a jelly-like battery that is rainbow coloured. Both teams want to compare how long their batteries last to a regular, silver AA battery.

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