A 2 Part question on Time and Work

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A 2 Part question on Time and Work

by e-GMAT » Tue Jan 01, 2013 9:29 pm
Hello Friends,

Please try this 2 part question.

A, B, & C can do the same job in 8, 24, & 48 hours respectively working individually. It was decided that each of them will work on this job alternatively for an hour. They can start the work in any order. Select 'Minimum hours', & 'Maximum hours' required to complete the job in the table. Make only two selections, one in each column.

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by Jim@StratusPrep » Fri Jan 04, 2013 2:53 pm
Nice question... Just a hint for those trying:

1/8 + 1/24 + 1/48 + 1/8 + 1/24 ...... keep up this sequence to find the fastest.
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by Jim@StratusPrep » Fri Jan 04, 2013 2:53 pm
The answer is when the sequent equals 1....
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by BTG14 » Tue Jan 15, 2013 11:19 pm
Step 1: in three hours : (1/8 + 1/24+ 1/48)=9/48.
Step 2: in (3*5) hours : 9*5/48=45/48. will be completed.

Now to be minimum let 45/48+1/8 which is more than 1. So the answer lies between 15 and 16.

Now to be maximum 45/48+1/48+1/24=1 which is 17 hours.

Answer will be : Minimum:15.5
Maximum 17 hours