document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1024180>Question 1024180</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A chemist needs 500 milliliters of a 20% acid and 80% water mix for a chemistry experiment. The chemist combines X milliliters of a 10% acid and 90% water mix and Y milliliters of a 30% acid and 70% water mix to make the 20% acid and 80% water mix. <BR>\n" );
document.write( "A. write a linear system that represents the situation. MY ANSWER: x+y= 500 -My teacher did part a in class.<BR>\n" );
document.write( "B. How many milliliters of the 10% acid and 90% water mix and the 30% acid and 70% water mix are combined to make the 20% acid and the 80% water mix? <BR>\n" );
document.write( "C. The chemists also needs 500 milliliters of a 15% acid and 85% water mix. Does the chemist need more of the 10% acid and 90% water mix than the 30% acid and 70% water mix to make this new mix? Explain.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #639639 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=639639\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A chemist needs 500 milliliters of a 20% acid and 80% water mix for a chemistry experiment. <BR>\n" );
document.write( "The chemist combines X milliliters of a 10% acid and 90% water mix and Y milliliters of a 30% acid and 70% water mix to make the 20% acid and 80% water mix.<BR>\n" );
document.write( "------<BR>\n" );
document.write( " <BR>\n" );
document.write( "A. write a linear system that represents the situation. MY ANSWER: x+y= 500 -My teacher did part a in class.<BR>\n" );
document.write( "Note: 10% fluid + 30% fluid = 100 milliliters<BR>\n" );
document.write( "acid + acid = acid<BR>\n" );
document.write( "------------------------------------ <BR>\n" );
document.write( "Quantity:: n + r = 100 ml<BR>\n" );
document.write( "Acid:::: 10n+30r = 20*100<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "n + r = 100<BR>\n" );
document.write( "n + 3r = 2*100<BR>\n" );
document.write( "--<BR>\n" );
document.write( "Subtract and solve for \"r\":: 2r = 100 ; r = 50ml (amt. of 30% solution needed)<BR>\n" );
document.write( "Then n = 100 - 50 = 50ml (amt. of 10% solution needed)<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "-----\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "B. How many milliliters of the 10% acid and 90% water mix and the 30% acid and 70% water mix are combined to make the 20% acid and the 80% water mix?<BR>\n" );
document.write( "Worked above.<BR>\n" );
document.write( "----------------<BR>\n" );
document.write( " <BR>\n" );
document.write( "C. The chemists also needs 500 milliliters of a 15% acid  mix. Does the chemist need more of the 10% acid mix than the 30% acid mix to make this new mix? Explain.<BR>\n" );
document.write( "Quantity: n + r = 500<BR>\n" );
document.write( "Acid:::: 10n+30r = 15*500<BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "n + r = 500<BR>\n" );
document.write( "n + 3r = 1.5*500<BR>\n" );
document.write( "---<BR>\n" );
document.write( "2r = 0.5*500<BR>\n" );
document.write( "r = 0.5*250 = 125ml (amt. of 30% needed)<BR>\n" );
document.write( "n = 500-125 = 375ml (amt. of 10% needed)<BR>\n" );
document.write( "==================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "------------ </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );