document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=640285>Question 640285</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a van travels 150 miles on 6 gallons of gas. write and solve a proportion to determine the number of gallons needed to travel 500 miles </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #403107 by </B><A HREF=/tutors/aboutme.mpl?userid=josh_jordan><B>josh_jordan(263)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josh_jordan><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=josh_jordan><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=403107\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We know that a van goes 150 miles per 6 gallons.  In other words:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150+miles%2F6+gallons+of+gas ALIGN=MIDDLE  ALT=\"150+miles%2F6+gallons+of+gas\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So, our proportion will look like this:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150+miles%2F6+gallons+of+gas+=+500+miles%2Fx+gallons+of+gas ALIGN=MIDDLE  ALT=\"150+miles%2F6+gallons+of+gas+=+500+miles%2Fx+gallons+of+gas\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Let's take out the words from our equation:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150%2F6+=+500%2Fx ALIGN=MIDDLE  ALT=\"150%2F6+=+500%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "When working with proportions (fractions) involving a variable, in this case x, we  can multiply the numerator on the left side by the denominator on the right, and multiply the denominator on the left side by the numerator on the right:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150%2Ax+=+6%2A500 ALIGN=MIDDLE  ALT=\"150%2Ax+=+6%2A500\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which gives us<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150x+=+3000 ALIGN=MIDDLE  ALT=\"150x+=+3000\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "We need to get x by itself on the left side of our equation, so we need to do the opposite of what's being done to x on the left side.  X is being multiplied by 150, so to get x by itself, we need to divide both sides by 150, since division is the opposite of multiplication:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28150x%29%2F150+=+3000%2F150 ALIGN=MIDDLE  ALT=\"%28150x%29%2F150+=+3000%2F150\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which equals\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+20 ALIGN=MIDDLE  ALT=\"x+=+20\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Therefore, 500 miles will use 20 gallons of gas </SPAN>\n" );
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