Question
Ravi and Sunil can complete a task in 12 days and 30
days respectively. Ravi started the task alone. After how many days should Sunil join him so that the task is completed in 10 days?Solution
ATQ,
Let the total work be 60 units (LCM of 12 and 30)
Efficiency of Ravi = 60 / 12 = 5 units/day
Efficiency of Sunil = 60 / 30 = 2 units/day
Let the time after which Sunil joined be n days.
So,
5n + (5 + 2) × (10 - n) = 60
5n + 70 - 7n = 60
-2n = -10
n = 5
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