document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1168709>Question 1168709</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Vinnie drives his car 156 miles and has average of a certain speed. If the average speed had been 5mph more. He could have traveled 168 miles jn the same length of time. What was his average speed? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #793324 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=793324\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The times are the same, so the ratio of distances is equal to the ratio of speeds:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=156%2F168+=+x%2F%28x%2B5%29 ALIGN=MIDDLE  ALT=\"156%2F168+=+x%2F%28x%2B5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "You can certainly solve this using formal algebra.  But you can also solve it (I think a bit more quickly) solving it using equivalent fractions.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=156%2F168+=+%2812%2A13%29%2F%2812%2A14%29+=+13%2F14 ALIGN=MIDDLE  ALT=\"156%2F168+=+%2812%2A13%29%2F%2812%2A14%29+=+13%2F14\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "In that simplified fraction the difference between the numerator and denominator is 1.  The problem tells us we want an equivalent fraction in which that difference is 5.  So get an equivalent fraction by multiplying numerator and denominator by 5:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13%2F14+=+%2813%2A5%29%2F%2814%2A5%29+=+65%2F70 ALIGN=MIDDLE  ALT=\"13%2F14+=+%2813%2A5%29%2F%2814%2A5%29+=+65%2F70\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWER: his average speed is 65mph (it would be 70mph if he had been driving 5mph faster).<br><BR>\n" );
document.write( " </SPAN>\n" );
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