A is twice as fast as B. If B alone can do a piece of work in 10 days, in what time can A and B together complete the work?
Select.
A) 10/3 B) 8 C) 9 D) 7/3 E) 12
A can do the work in10/2 i.e., 5 days.   A and B's one day's work = 1/5+ 1/10 = (2 + 1)/10 = 10/3   So A and B together can do the work in 10/3 days.   10/3nswer: 10/3
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A is twice as fast as B. If B alone can do a piece of work in 10 days, in what time can A and B together complete the work?