document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=208618>Question 208618</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average speed of today's plane is twice that of a plane of 5 years ago and takes  1 1/4 hours less time to fly the same distance of 1500 miles. find the average speed of a plane of 5 years ago ? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #157790 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=157790\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The average speed of today's plane is twice that of a plane of 5 years ago and<BR>\n" );
document.write( " takes 1 1/4 hours less time to fly the same distance of 1500 miles.<BR>\n" );
document.write( " find the average speed of a plane of 5 years ago?<BR>\n" );
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document.write( "let s = speed 5 yrs ago<BR>\n" );
document.write( "then<BR>\n" );
document.write( "2s = speed today<BR>\n" );
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document.write( "Write a time equation: Time = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dist%2Fspeed ALIGN=MIDDLE  ALT=\"dist%2Fspeed\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1500%2Fs ALIGN=MIDDLE  ALT=\"1500%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1500%2F%282s%29 ALIGN=MIDDLE  ALT=\"1500%2F%282s%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1.25<BR>\n" );
document.write( "Multiply 2s, results<BR>\n" );
document.write( "2(1500) - 1500 = 1.25(2s)<BR>\n" );
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document.write( "3000 - 1500 = 2.5s<BR>\n" );
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document.write( "1500 = 2.5s<BR>\n" );
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document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1500%2F2.5 ALIGN=MIDDLE  ALT=\"1500%2F2.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 600 mph speed 5 yrs ago<BR>\n" );
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document.write( "Check solution by finding the times<BR>\n" );
document.write( "1500/600 = 2.5 hrs<BR>\n" );
document.write( "1500/1200 =1.25 hrs<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "time diff: 1.25 hrs  </SPAN>\n" );
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