K alone can complete a work in 20 days and M alone can complete the same work in 30 days. K and M start the work together but K leaves the work after 5 days ofthe starting of work. In how many days M will complete the remaining work?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 35/2 days.
| Understanding/Application |
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Let total work to be done = L.C.M. (20,30) = 60 units K can complete it in 20 days K's efficiency = 60/20 = 3 units/day M's efficiency = 60/30 = 2 units/day Work done by them together in 5 days = (3 + 2) × 5 = 25 units |
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Let M complete the remaining work in x days. 25 + 2x = 60 2x = 35 x = 35/2 days |