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Can you solve this 'impossible' Maths question for 10-year-olds?

This took us hours to work out

Can you solve this 'impossible' Maths question for 10-year-olds?

There seems to be one of these going around the internet every five minutes, but this latest school maths question really had us stumped.

It was included on maths homework given to ten-year-old pupils in Year Five at a primary school in Glossop. But one dad asked Facebook for help after being at a loss to help his son with the baffling question.

The 43-year-old, who had A-levels in maths and economics wrote: “My son’s grandma had spent a while helping him with his homework and most of it was straightforward but this one question left her stumped. I then spent an hour or so trying to work it out but found it impossible. I even sent it to a friend who got a 1st class degree in economics and they were baffled by it as well. A couple of friends are maths teachers too so I’ve sent it to them but so far I’ve heard nothing back. I really do think it is impossible and it is certainly not something a ten-year-old can answer. It just does not make sense.”

Here are the questions:

Any ideas?

Well, it look us a long time to work it out, but we got there. We suggest that the University who dished out that first class economics degree should probably ask for it back too.

Here's how it's done:


You obviously know the lengths of the two sides marked 12cm and 10cm. So there's four other sides of unknown lengths.

However - two of them, marked in red, clearly add up to 10cm, as, together, they match the opposite side.


...while the other two - marked in blue, clearly add up to 12cm.

Add them all together - 12 (labelled) + 10 (labelled) + 10 (red) + 12 (blue) = 44cm.


The second one is slightly trickier. The three red lines here clearly add up to 9cm...


While these blue lines add up to 11cm....


Then you've also got these extra green bits - both 2cm in length.

Add everything together: 9 (labelled) + 11 (labelled) + 9 (red) + 11 (blue) + 2 + 2 (green) = 44cm

Easy peasy right? Right?