Answer:
5 1/4
Explanation:
Dividing by a fraction is the same as multiplying by its inverse.
(3 3/4)/(5/7) = (15/4)/(5/7) = (15/4)·(7/5) = 21/4 = 5 1/4
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Many graphing calculators (and some scientific calculators) will do this mixed-number arithmetic for you.