Working together A and B can do a job in 36 days, B and C in 10 days and all three together in 9 days. In how many days can B alone do the job?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 60
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Understanding |
Application |
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Working together A and B can do a job in 36 days, B and C in 10 days and all three together in 9 days. |
Suppose total work = 180 units (LCM of 36, 10 and 9) So, Efficiency of (A + B) = 180/36 = 5 Efficiency of (B + C) = 180/10 = 18 Efficiency of (A + B + C) = 180/9 = 20 Hence, Efficiency of C = 20 – 5 = 15 Efficiency of B = 18 – 15 = 3 Hence, Time in which B alone can complete = 180/3 = 60 days |