Question
Ajay alone can finish 60% of a task in 18 days. Vijay takes
15 days longer than Ajay to complete the entire task. When Vijay and Chirag work together, they can complete the full task in 20 days. How many days will Chirag alone take to finish the same task?Solution
ATQ;
Time taken by 'Ajay' alone to complete the entire work = 18 ÷ 0.6 = 30 days
Time taken by 'Vijay' alone to complete the entire work = 30 + 15 = 45 days
Let the total work = L.C.M of 30, 45 and 20 = 180 units
Then, efficiency of 'Vijay' = (180/45) = 4 units/day
Combined efficiency of 'Vijay' and 'Chirag' = (180/20) = 9 units/day
So, efficiency of 'Chirag' alone = 9 - 4 = 5 units/day
So, time taken by 'Chirag' alone to complete the entire work = (180/5) = 36 days
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