document.write( "Question 229250: how many liters of 75% gas and 90% gas would you need for 1200 liters of 85% gas? \n" ); document.write( "
Algebra.Com's Answer #169994 by checkley77(12844)\"\" \"About 
You can put this solution on YOUR website!
.90x+.75(1,200-x)=.85*1,200
\n" ); document.write( ".90x+900-.75x=1,020
\n" ); document.write( ".15x=1,020-900
\n" ); document.write( ".15x=120
\n" ); document.write( "x=120/.15
\n" ); document.write( "x=800 liters of 90% gas is used.
\n" ); document.write( "1,200-800=400 liters of 75% gas is used.
\n" ); document.write( "Proof:
\n" ); document.write( ".90*800+.75*400=1,020
\n" ); document.write( "720+300=1,020
\n" ); document.write( "1,020=1,020
\n" ); document.write( "
\n" );