document.write( "Question 400904: Here is the problem:\r
\n" ); document.write( "\n" ); document.write( "The cooling system of a car has a capacity of 15 liters. If the system is currently filled with a mixture that is 40% antifreeze, how much of this mixture should be drained and replaced with pure antifreeze so that the system is filled with a solution of 50% antifreeze?\r
\n" ); document.write( "\n" ); document.write( "I have to 1)define the variables, 2)set up the equation, 3)solve the equation, and 4)answer the question. I am having problems with 1 and 2, defining the variables and setting up the equation. Once I have those I can solve them and answer the questions.\r
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Algebra.Com's Answer #283726 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The cooling system of a car has a capacity of 15 liters.
\n" ); document.write( " If the system is currently filled with a mixture that is 40% antifreeze,
\n" ); document.write( " how much of this mixture should be drained and replaced with pure antifreeze
\n" ); document.write( " so that the system is filled with a solution of 50% antifreeze?
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\n" ); document.write( "Let a = amt of pure antifreeze bring the mixture up to 50%
\n" ); document.write( "Let a = also amt of existing mixture to be removed
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\n" ); document.write( "The equation (pure antifreeze would be 1a)
\n" ); document.write( ".40(15-a) + a = .50(15)
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