Math tricks can be a fun way to learn and teach basic rules of algebra. Impress friends by using numbers to do math tricks with tips from a mathematics tutor in this free video on math lessons.

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Math tricks can be a fun way to learn and teach basic rules of algebra. Impress friends by using numbers to do math tricks with tips from a mathematics tutor in this free video on math lessons.

Part of the Video Series: Math Games & Lessons

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Here is a good little trick that you can impress your friends with or even your parents. I wrote it down so that I don't forget any of the steps. Choose a number. Don't tell anyone what the number is. Add five to that number, double the result, then subtract four, then divide by two, the answer that you get here subtract the number that you started with, and you will always see that the result will always be three and you can check that with any number. For example, let's say that the number you chose is nine. Let's add five. We get fourteen. Let's double that result. That becomes twenty-eight. Let's subtract four. We get twenty-four. Divide by two. We get twelve and now subtract the number you started with which was nine and you'll see that you'll get a three. So no matter what number you choose, you'll always get a three and the reason for that is this is the foundation for algebra. Whatever you do to one side you do to the other, basic rule in algebra.