division

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Home : 2008 : March : 20

division
By BookMuncher

I'm not sure if I can explain it well in writing... AND-- not ever teaching an upper grade, I don't remember with is the divisor and which is the dividend, so I'm going to call them "the big number" and "the little number."
:rolleyes: People using Everyday math at your level probably will think I'm doing it all wrong-- this is simply my own personal understanding of it.

You know how when you multiply a number, you can do it in your head by multiplying the smaller number by the ones, tens, and hundreds of the larger number and adding that all up? Division is the opposite process. You can divide each

of the ones, tens, and hundreds by the smaller number and subtract to see what you've got leftover. Think of this as if you didn't have pencil and paper to do this problem, which I'm making up off the top of my head: 324 divided by 5.

First, how many times does 5 go into 320? 6 times. But I know that it's not exactly 6 times. (really a 60) There will be some left over. I know this because 60 times 5 is only 300. What's leftover will be 20. Actually-- 24 because of the four that's left in the original "big number". Now all I have left to do is work with what's leftover and divide it up the best I can, even if it's not even. 5 can go into 24, 4 times. Whole number answer is 64. But 5 times 4 is only 20. I'll have 4 left over. So the answer is 64 with 4 leftover. Why can't the remainder ever be bigger? Because if it were, I would have used it up and divided it.

That probably was next to impossible to follow. I don't know that I can explain to anyone, but anyone is capable of sitting down with some scratch paper and trying to figure out what they are doing. Try doing it WITHOUT the algorithm. You can still write, but you need to jot separate operations around the original problem. If you figure it out and learn it well, consider "playing" with division long before you teach it next year. Purposefully not showing them the algorithm until you have to, because when you do, they'll understand why each part works! Good luck! ;)