document.write( "Question 900021: How many gallons of 15% alcohol solution and 45% alcohol solution must be mixed to get 12 gallons of 25% alcohol solution? \n" ); document.write( "
Algebra.Com's Answer #545758 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
a+b=12,
\n" ); document.write( "0.15*a+0.45*b=0.25*12
\n" ); document.write( "a=12-b
\n" ); document.write( "0.15*(12-b)+0.45*b=3
\n" ); document.write( "1.8-0.15b+0.45*b=3
\n" ); document.write( "0.3*b=1.2
\n" ); document.write( "b=4
\n" ); document.write( "a=12-b
\n" ); document.write( "a=8 b=4
\n" ); document.write( "check
\n" ); document.write( "0.15*8+0.45*4=0.25*12
\n" ); document.write( "1.2+1.8=3
\n" ); document.write( "3=3
\n" ); document.write( "ok
\n" ); document.write( "
\n" ); document.write( "
\n" );