Question
A contractor decided to complete the work in 15 days and
employed 20 men at the beginning and 40 men additionally after 10 days and got the work completed as per schedule. If he had not employed the additional men, how many extra days would he have needed to complete the work?Solution
If he had not employed the additional men, then let work completes in T days. So as by chain rule, Men × time = constant So, 20 × 10 + (20+40) × 5 = 20 × T 200 + 300 = 20T T = 500/20 = 25 days So work delayed for = 25 - 15 = 10 days.
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