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This simple maths riddle is stumping the internet — see if you can solve it

Talia Lakritz
Wednesday 21 February 2018 08:42 EST
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The riddle begins: 'A man buys a horse...'
The riddle begins: 'A man buys a horse...' (Getty Images/iStockphoto)

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There's another viral math question stumping the internet.

The riddle was shared on parenting website and forum Mumsnet, where it racked up nearly 500 comments with other users debating the answer.

The text of the math question reads as follows:

A man buys a horse for $60. He sells the horse for $70. He then buys the horse back for $80. And he sells the horse again for $90. In the end, how much money did the man make or lose? Or did he break even?

Answers in the Mumsnet thread ranged from making $10, $20 and even $30, to breaking even. So what's the solution?

Can you work it out?
Can you work it out? (PeerieBreeks)

What seems to be throwing people off is the fact that the man sells the horse for $70 and then buys it back for $80, making it look like he spent 10 more dollars. But the correct way to solve the problem is to think of the two transactions as separate: -60 + 70 = 10 and -80 + 90 = 10.

The man makes $10 with each sale, therefore he earns a total of $20.

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Read the original article on Business Insider UK. © 2018. Follow Business Insider UK on Twitter.

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