Question
Ravi can finish a task in 18 days. If Ravi and Rohan
work together, they can complete the task in 10 days. How many days would Rohan alone take to finish the work?Solution
ATQ,
Let the total work be 90 units {LCM (18 and 10)}
Efficiency of Ravi = (90/18) = 5 units/day
Efficiency of Ravi and Rohan together = (90/10) = 9 units/day
Efficiency of Rohan = 9 - 5 = 4 units/day
Time required by Rohan to complete the work alone = (90/4) = 22.5 days
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