Question
Working alone, B can complete the work in 16 days. C is
twice as efficient as B and A takes 4 days more than it takes C to complete the work. Working together, in how much time would they be able to complete 13 such works?Solution
Time taken by B to complete the work = 16 days Time taken by C to complete the work = 16/2 = 8 days Time taken by A to complete the work alone = 8 + 4 = 12 days Work done by A, B and C together in 1 day. ⇒ (1/16 + 1/8 + 1/12) = (3 + 6 + 4)/48 = 13/48 this means if would take 48/13 days for A, B and C to complete the work together ∴ Time taken A, B and C to complete 13 works = 13 × 48/13 days = 48 days
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