1) 2 3/5 + 4 1/5 = (2 + 4) + (3/5 + 1/5) = 6 + 4/5 = 6 4/5
2) 3 1/2 + 5 3/4 = (3 + 5) + (1/2 + 3/4) = 8 + (2/4 + 3/4) = 8 + 5/4 = 8 + 1 1/4 = 9 1/4
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1) 7 5/8 - 4 1/3 = (7 - 4) + (5/8 - 1/3) = 3 + (15/24 - 8/24) = 3 + 7/24 = 3 7/24
2) 9 - 2 5/6 = 8 6/6 - 2 5/6 = (8 - 2) + (6/6 - 5/6) = 6 + 1/6 = 6 1/6