SOLUTION: Father can do the job on the farm in 6 hours. The older son can do it in 8 hours. The younger son can do same job in 12 hours. How long will it take them to do the job, if they all
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-> SOLUTION: Father can do the job on the farm in 6 hours. The older son can do it in 8 hours. The younger son can do same job in 12 hours. How long will it take them to do the job, if they all
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Question 1058532: Father can do the job on the farm in 6 hours. The older son can do it in 8 hours. The younger son can do same job in 12 hours. How long will it take them to do the job, if they all work together? Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! Add their rates of working
Their rates are:
[ 1 job ] / [ 6 hrs ]
[ 1 job ] / [ 8 hrs ]
[ 1 job ] / [ 12 hrs ]
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Let the rate of all 3 working together =
[ 1 job ] / [ t hrs ]
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Multiply both sides by hrs
and hrs = min
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Working together, they can do the job in 2 hrs 40 min
