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1 and 2/5 = 7/5
4 and 1/5 = 21/5, then
7/5/21/5 = 7/5 x 5/21 = 7/21 = 1/3
4 and 1/5 = 21/5, then
7/5/21/5 = 7/5 x 5/21 = 7/21 = 1/3