Basic Math & Pre-Algebra For Dummies
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With fractions, the relationship between the numbers, not the actual numbers themselves, is most important. Understanding how to multiply and divide fractions can give you a deeper understanding of why you can increase or decrease the numbers within a fraction without changing the value of the whole fraction.

When you multiply or divide any number by 1, the answer is the same number. This rule also goes for fractions, so

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When a fraction has the same number in both the numerator and the denominator, its value is 1. In other words, the fractions

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are all equal to 1. Look what happens you multiply the fraction

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The net effect is that you’ve increased the terms of the original fraction by 2. But all you’ve done is multiply the fraction by 1, so the value of the fraction hasn’t changed. The fraction 6/8 is equal to 3/4.

Similarly, reducing the fraction 6/9 by a factor of 3 is the same as dividing that fraction by 3/3 (which is equal to 1):

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So 6/9 is equal to 2/3.

About This Article

This article is from the book:

About the book author:

Mark Zegarelli is a professional writer with degrees in both English and Math from Rutgers University. He has earned his living for many years writing vast quantities of logic puzzles, a hefty chunk of software documentation, and the occasional book or film review. Along the way, he’s also paid a few bills doing housecleaning, decorative painting, and (for ten hours) retail sales. He likes writing best, though.

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