Question
A team leader can do a job as fast as three members of
the team working together. If one of the members can do the job in 5 hrs, the second one takes 10 hrs while the third one takes 25 hours for the same, how much time approximately is taken by the leader alone to complete the work?Solution
Work done by all the three members in 1 hour = 1/5 + 1/10 + 1/25 = (10+5+2)/50 = 17/50 part of the work ∴ Time taken by them to complete the work = 50/17 hrs ∴ Time taken by the leader = 50/17 hrs = 3 hrs (approx.)
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