document.write( "Question 206188: how many gallons of a 50% antifreeze solution must be mixed with 90 gallons of 15% antifreeze to get a mixture that is 40% antifreeze \n" ); document.write( "

Algebra.Com's Answer #155740 by Marth(57) $\"\"$ $\"About$

You can put this solution on YOUR website!
You have 90 gallons of a 15% antifreeze solution.
\n" ); document.write( "let x = the number of gallons of 50% antifreeze solution
\n" ); document.write( " $\"90%2A0.15+%2B+0.5x+=+0.40%2890%2Bx%29\"$
\n" ); document.write( "Solve for x.
\n" ); document.write( " $\"13.5+%2B+0.5x+=+36%2B0.4x\"$
\n" ); document.write( " $\"0.1x+=+22.5\"$
\n" ); document.write( "x = 225 gallons \n" ); document.write( "

\n" );