document.write( "Question 142043: The radiator in Michelle's car contains 16 L of antifreeze and water. This mixture is 30% antifreeze. How much of this mixture should she drain and replace with pure antifreeze so that there will be a mixture of 50% antifreeze? \n" ); document.write( "
Algebra.Com's Answer #103438 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The radiator in Michelle's car contains 16 L of antifreeze and water. This mixture is 30% antifreeze. How much of this mixture should she drain and replace with pure antifreeze so that there will be a mixture of 50% antifreeze?
\n" ); document.write( ":
\n" ); document.write( "Let x = amt drained and the amt added
\n" ); document.write( ":
\n" ); document.write( "Antifreeze amt added = 1.0x
\n" ); document.write( "Antifreeze mixture drained = .30x
\n" ); document.write( ":
\n" ); document.write( "Write an \"amt of antifreeze\" equation:\r
\n" ); document.write( "\n" ); document.write( "Original amt - drained amt + added amt = resulting amt
\n" ); document.write( ":
\n" ); document.write( ".30(16) - .30x + 1.0x = .50(16)
\n" ); document.write( ";
\n" ); document.write( "4.8 + .7x = 8
\n" ); document.write( ";
\n" ); document.write( ".7x = 8 - 4.8
\n" ); document.write( "x = \"3.2%2F.7\"
\n" ); document.write( "x = 4.57 L to be drained and replaced with pure antifreeze
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solution on a calc:
\n" ); document.write( "4.8 - (4.57*.3) + 4.57 = 7.999 ~ 8, which is .50(16)
\n" ); document.write( " \n" ); document.write( "
\n" );