<h3>
Explanation:</h3>
Unlike fractions: ones with different denominators.
Like fractions: ones with the same denominator.
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Examples:
1/3 and 1/4 are unlike fractions, because their denominators are different.
1/3 and 1/6 are also unlike fractions, because their denominators are different.
2/13 and 17/13 are like fractions, because their denominators are the same.
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<em>Comment on like/unlike fractions</em>
In general, addition and subtraction must be carried out on <em>like</em> fractions. That is, for unlike fractions to be added or subtracted, they must first be converted to like fractions. This is done by expressing both fractions using a common denominator. The common denominator is often chosen as the Least Common Multiple (LCM) of the two denominators, but it can be simply the product of the denominators:
a/b + c/d = (ad)/(bd) +(bc)/(bd) = (ad +bc)/(bd)
The reason for using the LCM of the denominators is that it <em>may</em> save work in reducing the final sum to lowest terms.
