document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=853679>Question 853679</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane travels from town A to town B at a constant speed of 400 mph and returns along the same route at a constant speed of 600mph. what is the plane's average speed for the round trip in miles per hours? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #514183 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=514183\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A plane travels from town A to town B at a constant speed of 400 mph and returns along the same route at a constant speed of 600mph.<BR>\n" );
document.write( " what is the plane's average speed for the round trip in miles per hours?<BR>\n" );
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document.write( "Let d = the one-way distance of the trip<BR>\n" );
document.write( "then<BR>\n" );
document.write( "2d = the round trip<BR>\n" );
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document.write( "Let a = the average speed for the round drip<BR>\n" );
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document.write( "Write time equation; time = dist;/speed<BR>\n" );
document.write( "AB time + BA time = total time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F400 ALIGN=MIDDLE  ALT=\"d%2F400\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F600 ALIGN=MIDDLE  ALT=\"d%2F600\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282d%29%2Fa ALIGN=MIDDLE  ALT=\"%282d%29%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "multiply equatin by 1200a, cancel the denominators and you have<BR>\n" );
document.write( "3ad + 2ad = 1200(2d)<BR>\n" );
document.write( "5ad = 2400d<BR>\n" );
document.write( "divide both sides by d<BR>\n" );
document.write( "5a = 2400<BR>\n" );
document.write( "a = 2400/5<BR>\n" );
document.write( "a = 480 mph av speed </SPAN>\n" );
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