Use equivalent fractions as strategy to add and subtract fractions.
Add and subtract fractions with unlike denominators (including mixed numbers) by replacing given fractions with equivalent fractions in such a way as to produce an equivalent sum or difference of fractions with like denominators. For example, 2/3+ 5/4=8/12 +15/12 = 23/12. (In general, a/ b+ c/d = a/d+b/c=bd) (5.NF.1)
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