Question 616519
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Hi,
takes Andrew 4 hours to clean the kitchen at camp. Daniel 3hrs...
How long {{{x}}} will it take them to clean it if they work together?
Note:  PER hour is the Key
  1/4 + 1/3 = 1/x     |Multiplying thru by 12x so as all denominators = 1
   3x+ 4x = 12
   7x = 12
    x = 12/7 hr