Add fractions using the least common denominator worksheets

What is on this worksheet

Add two fractions whose denominators do not divide each other, such as 2/3 and 3/4, so both must be rewritten with a common denominator.

• Denominators: Unlike (different)
• Operation: Add
• Unlike denominators: Neither divides the other

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About add and subtract fractions

With like denominators, students add or subtract the numerators and keep the denominator, including mixed numbers that need regrouping. With unlike denominators they find a common denominator first. For unlike denominators you can choose pairs where one denominator is a multiple of the other, pairs where neither divides the other, or both.

Like-denominator answers keep the denominator, so there is one correct form. Unlike-denominator answers are written in lowest terms, with mixed numbers for anything greater than 1. Subtraction never goes below zero.

Printing

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