Word Problem with Fractions
Date: 2/15/96 at 20:41:43 From: sigit Subject: finishing the job Jack can finish a job in 5 days, and Richard can finish the same job in 7 days. A job is to be done by Jack and Richard together. How long will it take them to finish this job ?
Date: 2/20/96 at 23:29:53 From: Doctor Byron Subject: Re: finishing the job We can reword this to say that Jack does 1/5 of a job in a day, and Richard does 1/7 of a job in a day. Together they complete 1/5 + 1/7 = 12/35 of a job in a day. The time it will take them to complete the job is simply the reciprocal of this value. (Just as we took the reciprocal to find the values above.) Therefore the job will take them 35/12 = 2 11/12 days. I hope this has helped. Good luck. -Doctor Byron, The Math Forum
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