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| Question 975820:  A petroleum company has two different sources of crude oil. The first source provides crude oil that is
 50%
 hydrocarbons, and the second one provides crude oil that is
 75%
 hydrocarbons. In order to obtain
 140
 gallons of crude oil that is
 60%
 hydrocarbons, how many gallons of crude oil must be used from each of the two sources?
 
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! A petroleum company has two different sources of crude oil. The first source provides crude oil that is 50% hydrocarbons, and the second one provides crude oil that is 75% hydrocarbons. In order to obtain 140 gallons of crude oil that is 60% hydrocarbons, how many gallons of crude oil must be used from each of the two sources?
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 Equation::
 carbon + carbon = carbon
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 0.50x + 0.75(140-x) = 0.60*140
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 50x + 75*140 - 75x = 60*140
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 -25x = -15*140
 x = (3/5)140
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 x = 3*28
 x = 84 gallons (amt of 50% oil needed)
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 140-x = 56 gallons (amt of 75% oil needed)
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 Cheers,
 Stan H.
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