C alone can complete a work in 20 days and D alone can complete the same workin 30 days. In how many days C and D together can complete the same work?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 12 days.
| Understanding/Application |
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C can complete work in 20 days. D can complete work in 30 days. |
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L.C.M of 20 and 30 = 60 Let the total work done be 60 units. Efficiency of C = 60/20 = 3 units/day Efficiency of D = 60/30 = 2 units/day Efficiency of C and D together = 5 units/day Time taken by C and D to complete work = 60/5 = 12 days |