Question
Person 'X' can complete a task in 30 days when working
at full efficiency, while person 'Y' can finish the same task in 50 days at full efficiency. If 'Y' works at only 62.5% efficiency and 'X' works at only 75% efficiency, how many days will it take for both 'X' and 'Y' to complete the task together?Solution
ATQ,
Time taken by 'X' to do the task with 100% efficiency = 30 days Time taken by 'X' to do the Task with 75% efficiency = 30 Γ (4/3) = 40 days Time taken by 'Y' to do the task with 100% efficiency = 50 days Time taken by 'Y' to do the task with 62.5% efficiency = 50 Γ (8/5) = 80 days Task done by both in one day = (1/40) + (1/80) = (3/80) Total time taken to complete the task = (80/3) days
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