Teacher2Teacher Q&A #5245

Multiplication with your ten fingers

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From: Jeanne (for Teacher2Teacher Service)
Date: Nov 30, 2000 at 21:31:19
Subject: Re: Multiplication with your ten fingers

I learned how to multiply 6 x 6 on up to 10 x 10 several years ago. The challenge is how to describe it so the you can "see it" given the fact that I am unable to draw pictures for you. Well here goes... Example: 8 x 9 (The 8 will be on your left hand. The 9 will be on your right hand.) Open your hands so that the palms are up. Left hand: Fold in your thumb, your index finger, and your middle finger. Right hand: Fold in your thumb, your index finger, your middle finger and your ring finger. You have 7 fingers and thumbs folded in. This represents 70. You have 2 fingers up on your left and and 1 finger up on the right. This represents 2. (2 x 1 = 2) 8 x 9 = 70 + 2 = 72. Here's another example: 6 x 6 Left hand: Fold in your thumb. Right hand: Fold in your thumb. You have 2 fingers and thumbs folded in: 20. You have 4 fingers up on your left hand and 4 fingers up on your right hand. This represents 16. (4 x 4 = 16) 6 x 6 = 20 + 16 = 36. In case you are wondering why this works.........I have no clue. Anyway, thanks for asking this question. It was fun to remember the teacher who taught this to me so many years ago. -Jeanne, for the T2T service

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