viral maths puzzle

If you want your brain to ache, this viral store theft puzzle has got everyone stressed out

I need to go and have a lie down


Another day, another random maths puzzle goes viral on Twitter – this one’s all about money and stolen goods. Not only is it about petty theft and the maths of change, it’s also causing a frenzy in the replies about what is actually the right answer. I had honestly no clue what I’d go for for the answer, so I’m taking the top reply as bible. The viral maths puzzle is basically to find out how much the store lost in total.

What is the viral maths puzzle?

The puzzle reads as follows: “A man steals $100 from a store’s register. Then he buys $70 worth of goods at that store using the $100 bill and gets $30 change. How much money did the store lose?”

The top reply to the tweet seemingly has the right answer. “The store lost $100, then they got $100 back. So far, store lost 0. Then the store had to give $30 back in change, so the store lost $30 in cash and then the $70 in goods. It lost $100 in total including cash and goods.”

Right, I get all that.. but I think, and maybe I’m thinking too deeply here, but if the money is being taken from the register then it’s likely not been cashed up yet into the shop’s funds. So has the shop lost more?

One guy in the replies said we don’t have enough info for the actual truth, which is making me wonder if I’ll ever get a sleep filled night again. “Not enough info. Depends upon cost of goods sold, and whether they reported it to their insurance company.” WELP.

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Photo by Giorgio Trovato on Unsplash before edits.