A can do a piece of work in 14 days and B is 40% more efficient than A. In how many days can B finish it?
Number of days required by A to finish the work : 14 days
Work done by A in one day: 
B can work 40% more efficiently than A,
B's one day work = 140% of 
= 
B alone can complete the work in 10 days.
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