Question
35 people working 7 hours a day take 22 days to complete
a task. How many people working for 6 hours a day are needed to complete five times the given task in 40 days if they work at 30% higher efficiency? (can calculate approximate value)Solution
Original work = 35 people Ă 7 hrs/day Ă 22 days = 5390 man-hours New task = 5 times the original = 26950 man-hours New workers: work 6 hrs/day for 40 days, but 30% more efficient, so effective = 7.8 hrs/day Total work each person can do = 7.8 Ă 40 = 312 hrs Let number of people = x, so total work = 312x=26950 Solving: x = 26950 á 312 â 86.37 or 87
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