Dividing Three Digit Numbers
From: "Barbara A. Shaw" Subject: Help Dear Dr. Math, I am in 7th grade. I don't understand how to divide by 3 digit numbers. Can you help me? Please reply. My e-mail address is: firstname.lastname@example.org Please write Maira in the Subject line. Thank you. Maira Rosales Takoma Education Center Washington, DC
From: Dr. Ethan Date: Thu, 3 Nov 1994 10:31:28 -0500 (EST) Hi Maira, I must say that I think that dividing is hard as well, but it is worth it once you have learned it. Here is how I do it; I hope that it helps you. Let's look at an example to help us get started. ____ 324/3566 Okay, now let's divide. The first step is to look at 324 and the first three digits of the other number. They are 356. Now we need to ask ourselves will 324 go into 356? Yes, because 356 is bigger. How many times do you think it will go in? I think that it will go in only once because 356 isn't very much bigger than 324. So I write 1 on the top and it looks like this: __1__ 324/3566 Now multiply 1 times 324 and bring it down below to see what is left over. 1 times 324 is 324 so we get __1__ 324/3566 324 Then we subtract 324 from 356 and we get 32. Then bring that down and bring down the 6 to get __1__ 324/3566 324_ 0326 Now check if 324 goes into 326. It does just barely. It only goes in once, so we repeat the above process to get __11_ 324/3566 324_ 0326 324 2 324 does not go into 2 so that is the remainder. I hope that this was helpful. If you have more questions or want more help on division, please write back. Ethan-Doctor On Call
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