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Double Helix Extra readers really got busy with brainteasers in 2024! Let’s do a count down of your top 5…

Here are eight 8s, 8 8 8 8 8 8 8 8. Put some plus signs in there to make 1000.

A famous person built a square house so that the windows on all four sides look south. Where is this house? (And can you name the famous person?)

Farmer Doolittle has a farm with just cows and chickens. The farmer counts up all the animals and discovers that there are 43 heads and 120 legs on the farm (not counting the farmers). How many cows live on farmer Doolittle’s farm?

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.

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?

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?

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.

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.

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