SOLUTION: There is a series of project activities to be performed by two staff members, Mr. X and Mr. Y. When each of them works alone, it can be completed by Mr. X in 3 hours and by Mr. Y
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-> SOLUTION: There is a series of project activities to be performed by two staff members, Mr. X and Mr. Y. When each of them works alone, it can be completed by Mr. X in 3 hours and by Mr. Y
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Question 1088782: There is a series of project activities to be performed by two staff members, Mr. X and Mr. Y. When each of them works alone, it can be completed by Mr. X in 3 hours and by Mr. Y in 6 hours. When Mr. X starts to work at 9:00 a.m. and then Mr. Y starts to work with Mr. X at 10:00 a.m., which of the following is the time at which all the activities are completed? Here, the activities can be divided and performed in parallel by the two members without any loss of productivity.
From 9:00 am to 10:00 am, Mr.X will complete of the activity, so will remain uncompleted.
The rate of work for X is of the job per hour.
The rate of work for Y is of the job per hour.
So, their combined rate of work is {{1/3+1/6}}} = = = of the job per hour.
Thus they need = = hours = 1 hour and 20 minutes to complete the job.
So, Mr.X and Mr.Y will complete their activity 1 hour and 20 minutes after 10:00 am, i.e. at 11:20 am.
