How to Divide Decimals by Decimals
Date: 03/07/98 at 19:16:53 From: Tiffany Wright Subject: dividing decimals I don't understand dividing decimals. Can you send me any information so I can understand it more? Thank you! Tiffany Wright
Date: 03/08/98 at 11:33:30 From: Doctor Lim Subject: Re: dividing decimals Dear Tiffany, Don't worry. Doing mathematics problems is just like eating a piece of cake. Eating a piece of cake gets difficult when we try to eat a big piece of cake all in one gulp. Let's break it into smaller pieces, and we can eat it easier. Start with dividing a one-place decimal into another one-place decimal: 0.2/0.5 It actually means ____ 0.5 )0.2 We cannot have a divisor that is not a whole number, so we must change 0.5 into a whole number. To do this, we have to multiply by 10. This is because 0.5 is in the tenths place. We have to do this for both the divisor and the dividend in order to balance them. 0.2 x 10 2 ------------- = ----- 0.5 x 10 5 So, we have ____ 5 )2.0 We need to show where the decimal point is in the dividend. The next thing we need to do is to fix the decimal point of the answer. What you do is just to move another decimal point straight up from the position in the dividend. ___.___ 5 ) 2.0 So, now you do normal division. Does 5 go into 2? No, so you can either leave it blank, or put a zero there to remind yourself there's nothing there (and it will ensure that you keep your decimal point in the right place). Does 5 go into 20? Yes, so we put a 4 above the zero. Our final answer is .4. Now let's go through a more complicated problem: ______ 0.14 )0.448 As above, we check out the divisor. The divisor is 0.14, which is 14 hundredths. So we have to multiply by 100. 0.448 x 100 44.8 ------------------- = ---------- 0.14 x 100 14 The first thing we do is take care of the decimal point of the divisor (multiply by 100). So, we move the decimal of the dividend over two places. Now we have ______ 14 )44.8 Position the decimal point, ___.__ 14 )44.8 xx.x ------- xx.x Once you have positioned the decimal point, divide the numbers as usual. You should have no problem, because it is the same as division of a big number, 448, divided by a smaller number, 14. The only difference is that in your answer, you have to remember the position of the decimal point. Take things easy. Once you practise more often, you will find that it gets easier and easier. Maths then will become a breeze. -Doctor Lim, The Math Forum Check out our web site http://mathforum.org/dr.math/
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