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Hi, I'm Zoya Popova for About.com, and today we're going to talk about fractions.Put quite simply, a fraction is a type of number. They are numbers that represents parts of a whole. Now, when we talk about fractions, we usually refer to common fractions. A common fraction is a number that is written down as a whole number divided by another whole number that is not a zero. 2/3 is an example of a common fraction, with the whole number 2 in the top divided by the whole number 3 in the bottom.The top number is known as the numerator, and the bottom number is known as the denominator. So let's take look at this apple. For the fraction 2/3, the denominator is 3, and what it tells us is that the apple has been cut into 3 equal parts. The numerator is 2, and that tells us that we're dealing with 2 of those 3 equal parts.An important distinction is proper fractions versus improper fractions. In a proper fraction, the numerator is smaller than the denominator. For instance, in 7/8, 7 is smaller than 8; and in -2/15, 2 is smaller than 15. Improper fractions have an absolute value of less than 1. In an improper fraction, the numerator is greater than the denominator, such as 17/12. Now, it is obvious that the absolute value of this fraction is greater than 1, because 17 twelfths already contain 12 twelfths, plus an additional 5 twelfths.Any improper fraction can be presented as a combination of a whole number and a proper fraction:17/12=(12+5)/12=12/12+5/12=1+5/12To convert an improper fraction into a mixed fraction, divide the numerator by the denominator to get a whole quotient. For us, the quotient is 1—that will be the whole part of our mixed fraction. When, in our division process, we get to the remainder, which in our case is 5, that will be the numerator of our proper fraction.To convert a mixed fraction into an improper fraction, do the same process in reverse. For example, to convert 3 and 2/3, multiply the denominator by the whole part and add the numerator: 3*3+2=11. This will become the numerator of the improper fraction. The denominator will stay the same. So 3 and 2/3 equals 11/3.And always remember to convert mixed fractions into improper fractions before you add, subtract, multiply, or divide fractions. And this is it for our fractions today.
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