Question 633418
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Hi,
i can do a job in 4 hour and we can do the same job in 2 hour
how long  {{{highlight(x)}}}can you do the job alone?
Question states***PER hour Key
 1/4 + 1/x = 1/2    |Multiplying thru by 4x so as all denominators = 1
  x + 4 = 2x
      4hr = x

and...
 {{{1/4 + 1/4 = 1/2}}}