document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=257068>Question 257068</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi i had 2 questions.  My first question is this. How many gallons of pure alcohol should be mixed with 20 gal of a 15% alcohol solution to obtain a mixture that is 25% alcohol? I have done this problem several times and i get as far as .15x + 3 = .25x + 5 but i keep getting a negative answer. Could you please show me how to solve this correctly.  My other question is this Marin Caswell needs 10% hydrocholoric acid for a chemistry experiment. How much 5% acid should mix with 60 mL of 20% acid to get a 10% solution? I really want to know how to solve these and set them up so i can do them on the test.  Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #189058 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=189058\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many gallons of pure alcohol should be mixed with 20 gal of a 15% alcohol solution to obtain a mixture that is 25% alcohol?<BR>\n" );
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document.write( "Let x = amt of pure alcohol required<BR>\n" );
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document.write( "A per cent equation<BR>\n" );
document.write( ".15(20) + 1x = .25(x+20)<BR>\n" );
document.write( "3 + 1x = .25x + 5<BR>\n" );
document.write( "1x - .25x = 5 - 3<BR>\n" );
document.write( ".75x = 2<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F.75 ALIGN=MIDDLE  ALT=\"2%2F.75\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "x = 2<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3 ALIGN=MIDDLE  ALT=\"2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > gal of pure alcohol required<BR>\n" );
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document.write( "Marin Caswell needs 10% hydrocholoric acid for a chemistry experiment.<BR>\n" );
document.write( " How much 5% acid should mix with 60 mL of 20% acid to get a 10% solution? <BR>\n" );
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document.write( "Let x = amt of 5% mixture required<BR>\n" );
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document.write( ".05x + .20(60) = .10(x+60)<BR>\n" );
document.write( ".05x + 12 = .10x + 6<BR>\n" );
document.write( "12 - 6 = .10x - .05x<BR>\n" );
document.write( "6 = .05x<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2F.05 ALIGN=MIDDLE  ALT=\"6%2F.05\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 120 ml of 5% stuff<BR>\n" );
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document.write( "Prove this<BR>\n" );
document.write( ".05(120) + .20(60) = .10(120 + 60)<BR>\n" );
document.write( "6 + 12 = .10(180)<BR>\n" );
document.write( "18 = 18<BR>\n" );
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document.write( "You can prove the 1st one, like we did this one.  </SPAN>\n" );
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