Thursday, January 11, 2018

Multiplication Patterns (Tricks)

All of third grade is working on their multiplication table memorization! Here are some tricks for memorizing some of the facts. Hope this helps and see you tomorrow!

 is just doubling the number. The same as adding the number to itself. 
2×2=4, 2×3=6, 2×4=8, etc.
So the pattern is 2, 4, 6, 8, 10, 12, 14, 16, 18, 20
(And once you remember those, you also know 3×2, 4×2, 5×2, etc., right?)
 
 has a pattern: 5, 10, 15, 20, etc. It ends in either 0 or 5.


 has a pattern, too: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90
Now, notice how the "ones" place goes down: 9,8,7,6, ...? And at the same time, the "tens" place goes up: 1,2,3,...? Well, your hands can help!
Example: to multiply 9 by 8: hold your 8th finger down, and you can count "7" and "2" ... the answer is 72

10× is maybe the easiest of them all ... just put a zero after it. 10×2=20, 10×3=30, 10×4=40, etc. 

11× is mostly easy: from 11×2 to 11×9 you just put the two digits together. 11×2=22, 11×3=33, ..., 11×9=99.

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