document.write( "Question 611248: A petroleum company has two different sources of crude oil. The first source provides crude oil that is 25% hydrocarbons, and the second one provides crude oil that is 75% hydrocarbons. In order to obtain 50 gallons of crude oil that is 55% hydrocarbons, how many gallons of crude oil must be used from each of the two sources?
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Algebra.Com's Answer #384871 by stanbon(75887)\"\" \"About 
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The first source provides crude oil that is 25% hydrocarbons, and the second one provides crude oil that is 75% hydrocarbons. In order to obtain 50 gallons of crude oil that is 55% hydrocarbons, how many gallons of crude oil must be used from each of the two sources?
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\n" ); document.write( "Equation:
\n" ); document.write( "hydro + hydro = hydro
\n" ); document.write( "0.25x + 0.75(50-x) = 0.55*50
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\n" ); document.write( "25x + 75*50 - 75*x = 55*50
\n" ); document.write( "-50x = -20*50
\n" ); document.write( "x = 20 gallons (amt. of 25% oil needed)
\n" ); document.write( "50-x = 30 gallons (amt. of 75% oil needed)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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