A viral video of a mind-blasting maths puzzle has left thousands of people stumped as they attempted to solve the mystery. It involves a sum that is mathematically incorrect and all you have to do is make it correct - but there’s a catch.
You’re only allowed to add one line. A clip, shared online, shows the puzzle starting off as an incorrect sum that claims 5 + 5 + 5 = 550. Your task is to make the sum correct by adding just one line - and it's not as easy as it might seem at first glance, the Mirror reports.
The clip, which was shared on TikTok by @xivecct75, shows a man explaining the task to his wife, who then attempts to solve the puzzle in all the ways that make sense to her, including using her one line to make the number 1, changing one of the 5s to a 15 or to a 51 - although neither bring her to the correct solution.
The man says in the video: "With one line, I want you to make this addition equation correct. Only one line.
After realising that creating a 15 or 51 won't work, the woman then tried to connect the bottom of one of the 5's to make it look more like a 6, although that didn't work either.
Then, the woman had a breakthrough as she thought she had arrived at the right solution when she said she could put a line through the equals sign to create the 'does not equal' sign, which would state that 5 + 5 + 5 does not equal 550.
But the man told her: "No, no, no. That may be true, but that is not a correct addition equation. The goal is to make this whole equation correct."
Defeated, the woman gave up on the puzzle, and her husband was about to give her the answer when her son picked up the piece of paper and solved it for her - leaving her stunned.
The solution was to draw one vertical line to the side of the first plus sign to turn it into a 4, which in turn made the equation read 545 + 5 = 550.
Commenters on the video - which has been viewed over 3.4 million times - were divided over the puzzle, as while some of them claimed it was "easy", many others said they were left stumped before they had watched the solution.
One person said: "That boy is me. Come on, this is easy!" While another added: "Mind blasting!" As someone else posted: "I've seen this several times and I still forget how it's done the next time." "I never would have gotten that", a fourth wrote.
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