<PRE><B>Question 406717</B>
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Hi
To supply a small factory with enerygy costs $580 per week when it is open 5
 days a week for 8 hours a day. Find how much energy it will cost to supply the
 factory with energy if the working day is extended to 9.5 hours?
Let x represent cost for 9.5hr working day
Question states*** Sets Up the Proportion
 {{{$580/40 = x/ 47.5}}}
Solving for x by cross multiplying
  40x = $580*47.5
    x = $580*47.5/40
    x = $688.75
CHECKING our Answer***
 {{{$580/40 = 14.5 =  688.75/ 47.5}}}
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