Scientific American presents Math Dude by Quick & Dirty Tips. Scientific American and Quick & Dirty Tips are both Macmillan companies.

After all of the fun we’ve had recounting the tales of Knot Dude, Papa Knot, seafaring pyramid builders, and the loads and loads of algebraic goodness they all used in their adventures, it’s time to shift our attention elsewhere for a while and talk about some practical and easy techniques that you can use to do simple math in your head…and to do it fast! Leading things off this week, we’re going to learn how to quickly calculate the square of any number. Keep on reading to find out how to do it!

Why Mental Math?
Before we start turning you into a mental math genius, it’s worth taking a minute or two to talk about why learning mental math is useful…and actually really, really important. In short, learning to recognize the patterns behind simple mental math problems makes you mathematically savvier. Not only will this help you impress your friends, calculate tips, make sure the cashier gives you the correct change, and lots of handy things like that, being mathematically savvy will also help ensure your future financial security.

In fact, a recent study published in the Proceedings of the National Academy of Sciences found that people who lacked the ability to solve simple math problems were much more likely to default on their home mortgage. One of the easiest and most fun ways to get comfortable with numbers and basic math is to learn mental math tricks, which, according to this study, means that learning mental math skills is also one of the best ways to make sure that you invest wisely in the future.


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