SOLUTION: Antonio, an experience shipping clerk, can fill a certain order in 5 hours. Brian, a new clerk, needs 9 hours to do the same job. working together, how long would it take them to f

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Antonio, an experience shipping clerk, can fill a certain order in 5 hours. Brian, a new clerk, needs 9 hours to do the same job. working together, how long would it take them to f      Log On


   



Question 681476: Antonio, an experience shipping clerk, can fill a certain order in 5 hours. Brian, a new clerk, needs 9 hours to do the same job. working together, how long would it take them to fill the order..... can someone help me solve this problem please:)

Answer by tomlaidlaw(14) About Me  (Show Source):
You can put this solution on YOUR website!
You have to think kind of upside down. Antonio can do 1/5 of the job in one hour. Brian can do 1/9 of the job in one hour. Add them together
1%2F5+%2B+1%2F9+=+1 Lowest common denominator is 9 x 5= 45. So 1/5 = 9/45 and 1/9 = 5/45. The total is 14/45 of the job can be done in one hour. Another way to say that is that it will take 45/14 of an hour to get the job done. Divide 45 by 14 and get 3 and 3/14 hours. Multiplying 3/14 by 60 gives 12.86 minutes, so the total job will be done in 3 hours-12.86 minutes.
Tom Laidlaw