Question
A and B together can complete a task in 12 days, while A
alone can complete the same task in 20 days. If A and B start the work together, but B leaves after 8 days, in how many more days will A complete the remaining work?Solution
Work done by A and B in 1 day = 1/12 Work done by A alone in 1 day = 1/20 Work done by B in 1 day = 1/12 - 1/20 = 1/30 Work completed in 8 days by A and B = 8 × 1/12 = 2/3 Remaining work = 1 - 2/3 = 1/3 Time taken by A to complete remaining work = (1/3) ÷ (1/20) = 20/3 = 6.67 days. Correct answer: a) 6.67 days
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