document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=755383>Question 755383</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Peter drives from his home to the store at an average speed of 40 miles per hour. He returns home along the same route at an average speed of 60 miles per hour. What is his average speed in miles per hour for the entire trip? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #459633 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=459633\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Peter drives from his home to the store at an average speed of 40 miles per hour. <BR>\n" );
document.write( "He returns home along the same route at an average speed of 60 miles per hour.<BR>\n" );
document.write( " What is his average speed in miles per hour for the entire trip?<BR>\n" );
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document.write( "let a = his average speed for the round trip<BR>\n" );
document.write( "let d = the one way distance<BR>\n" );
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document.write( "Write a time equation; time = dist/speed<BR>\n" );
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document.write( "Go time + return time = total time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F40 ALIGN=MIDDLE  ALT=\"d%2F40\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F60 ALIGN=MIDDLE  ALT=\"d%2F60\"   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( "We can get rid of the denominators by mult by 120a, resulting in<BR>\n" );
document.write( "3ad + 2ad = 120(2d)<BR>\n" );
document.write( "5ad = 240d<BR>\n" );
document.write( "divide both sides by d<BR>\n" );
document.write( "5a = 240<BR>\n" );
document.write( "a = 240/5<BR>\n" );
document.write( "a = 48 mph is the av speed for the round trip<BR>\n" );
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document.write( "We can confirm this solution, assume one way is 60 mi, then we have<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=60%2F40 ALIGN=MIDDLE  ALT=\"60%2F40\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2F60 ALIGN=MIDDLE  ALT=\"6%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28120%29%2F48 ALIGN=MIDDLE  ALT=\"%28120%29%2F48\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "do the math<BR>\n" );
document.write( "1.5 + 1 = 2.5 </SPAN>\n" );
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