A factory worker produced one lot of connecting clips, and initial quality control found that $$\frac{5}{7}$$ of clips in the lot could be used. An assembly plant purchased this lot of clips valuing the lot at $3 per each usable clip. During assembly, it became known that only $$\frac{3}{5}$$ of the clips in the lot were usable. What was price per usable clip that the assembly plant paid for the lot?
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A$$${2}\frac{1}{7}$$
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B$$${3}\frac{4}{7}$$
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C$$${5}\frac{1}{4}$$
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D$5
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E$$${6}\frac{3}{8}$$
显示答案
正确答案: B