And impress your friends while you’re at it.
Many children count on their fingers when they are first learning math. Fingers are a great tool that you always have at your disposal, after all. But did you know that your fingers can be used to do multiplication as well as addition?
You can multiply any number from 1 – 10 by 9 using nothing but your two hands. Start by holding them out in front of you. Pick a number and fold down that finger (counting from the left). Now look at the number of fingers to the left of the folded one — that’s your 10s digit. Look at the number of fingers to the right of your folded one — that’s your 1s.
Let’s try an example: If you want to multiply 9 by 7, you would fold down your seventh finger. To the left of it will be 6 fingers and to the right of it will be 3 fingers so 9 x 7 = 63. Easy, right?
You may also notice that the two digits will always add up to 9 — your ten fingers minus the one you folded down.
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