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| Question 972287:  Dale can finish 12kg laundry in 5 hours while Jim can finish 8.4 kg laundry in 4 hours. If they work together, how long will they be able to finish 18 kg laundry?
 Answer by josgarithmetic(39630)
      (Show Source): 
You can put this solution on YOUR website! Laundry is done in batches, so uniform work rates is a bad way to model such a job.  The size of the laundry and the time for doing it have a relationship.  If Dale and Jim work together, then they finish in about maybe 6 or 7 hours.  Jim finishes first, and he may then help Dale, but this would not do much for time saving. 
 Look best at it this way:
 
 size____________time
 8.4_____________4
 12______________5
 18______________?
 
 What kind of fit should this be? You could try and assume a linear fit.  Size determines time.  Expect about 8.6 hours for an 18 kg laundry.
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