When I was in the fourth grade I was supposed to memorize the multiplication tables, but I never bothered. Some I know pretty good, some I can come up with if I think about it hard enough, and some are a lost cause -- fours, sixes, sevens, and eights are especially hard for me.
I get around it by adding things up. For example, if I need to multiply 7 x 6, I would multiply 7 times 3 (21) and add 21 to 21 to get 42.
The other day I was figuring how many tablespoons there are in a pound of butter. There are 8 tablespoons per stick, and 4 sticks. I couldn't remember how much 8 x 4 is, but I do know 8 x 8 is 64, and half of 8 is 4, so 8 x 4 would be half of 64, which is 32. Did you get that?
Nines are easy -- you just multiply by ten and subtract, as in 6 x 9: 6 times 10 is 60, so 6 times 9 would be 60 minus 6, or 54.
The really nasty bugaboo is 8 x 6. I was taught, back there in the fourth grade, that 8 x 6 (or, conversely, 6 x 8) is equal to the number of stars in the flag. So 6 x 8 must be 50. Somehow that never seems to turn out exactly right.
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