All of third grade is doing stellar job on their multiplication! We will begin to incorporate these facts into a fun memorization incentive beginning next week! Here are some tricks for memorizing some of the facts. Hope this helps for your test tomorrow and for our future incentive! :)
2× is just doubling the number. The same as adding the number to itself.
5× has a pattern: 5, 10, 15, 20, etc. It ends in either 0 or 5.
9× has a pattern, too: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90
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.
2× 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?)
9× 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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