Multiplying a Fraction by a Decimal
Date: 9/5/96 at 13:8:48 From: Glenn Hill Subject: Fraction Times a Number How do I simplify and multiply: 40 ----- x 78.5 360
Date: 9/6/96 at 4:20:55 From: Doctor Mike Subject: Re: Fraction Times a Number Hi Glenn, There are several ways to do this. If you have a calculator, you could do 40/360 first, and then multiply that by 78.5 . If you are doing it by hand, then the easiest way is to first reduce the fraction to lowest terms. The numerator 40 and the denominator 360 are both multiples of 10, so you could divide both numerator and denominator by 10 to get the equivalent fraction 4/36 . Since 4 times 9 is 36, this fraction is equivalent to 1/9 . Your original problem is now 1 --- x 78.5 9 That is the same as 78.5/9 which you can do on paper with long division. Either way the answer is an infinitely repeating decimal 8.722222222... . A good approximate value is 8.722. I hope this helps. -Doctor Mike, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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