document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=465792>Question 465792</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bob drove 408 miles using 15 gallons of gas. At this rate, how many gallons of gas would he need to drive 340 miles? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #319189 by </B><A HREF=/tutors/aboutme.mpl?userid=kingme18><B>kingme18(98)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=kingme18><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=kingme18><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=319189\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can solve this using a proportion, which basically means a fraction = a fraction.  For both, I'm going to put the number of miles over the number of gallons; if you want, you can put gallons over miles as long as you do it both times.  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=408%2F15=340%2Fx ALIGN=MIDDLE  ALT=\"408%2F15=340%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  My favorite way to solve this is to do cross multiplication: multiply the top left with the bottom right, and multiply the bottom left with the top right.  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=408%2Ax=15%2A340 ALIGN=MIDDLE  ALT=\"408%2Ax=15%2A340\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Simplify: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=408x=5100 ALIGN=MIDDLE  ALT=\"408x=5100\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Divide by 408 on both sides to get x by itself, and your final answer is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=12.5 ALIGN=MIDDLE  ALT=\"x=12.5\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "I like to go back and check by doing the division on both sides and making sure I get the same thing for both: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=408%2F15=27.2 ALIGN=MIDDLE  ALT=\"408%2F15=27.2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=340%2F12.5=27.2 ALIGN=MIDDLE  ALT=\"340%2F12.5=27.2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Both fractions equal 27.2, so we're definitely right! </SPAN>\n" );
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