document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=522689>Question 522689</A>: <I><SPAN STYLE=\"word-break: break-all;\"> David is traveling to the airport to catch a flight, if he travels at the speed of 30 mph, he is late by 13 minutes. If he travels at the speed of 40 mph, he will arrive 7 minutes earlier than the scheduled departure time of the flight. What is the distance to the airport (in miles)? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #346973 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=346973\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> David is traveling to the airport to catch a flight, if he travels at the speed of 30 mph, he is late by 13 minutes.<BR>\n" );
document.write( " If he travels at the speed of 40 mph, he will arrive 7 minutes earlier than the scheduled departure time of the flight.<BR>\n" );
document.write( " What is the distance to the airport (in miles)?<BR>\n" );
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document.write( "Let d = distance to airport<BR>\n" );
document.write( "Let s = speed required to arrive on time<BR>\n" );
document.write( "then<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2Fs ALIGN=MIDDLE  ALT=\"d%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the ideal time to the airport<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation for each scenario<BR>\n" );
document.write( ":<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F30 ALIGN=MIDDLE  ALT=\"d%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2Fs ALIGN=MIDDLE  ALT=\"d%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13%2F60 ALIGN=MIDDLE  ALT=\"13%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" >; late<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%2Fs ALIGN=MIDDLE  ALT=\"d%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2F60 ALIGN=MIDDLE  ALT=\"7%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" >; early<BR>\n" );
document.write( "--------------------------------------- addition, eliminates d/s<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F30 ALIGN=MIDDLE  ALT=\"d%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <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;\" > + 0 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2F60 ALIGN=MIDDLE  ALT=\"20%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Clear denominators, multiply by 120, results:<BR>\n" );
document.write( "4d - 3d = 2(20)<BR>\n" );
document.write( "d = 40 mi to the airport<BR>\n" );
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document.write( ":<BR>\n" );
document.write( "See if this works; find s<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2F30 ALIGN=MIDDLE  ALT=\"40%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2Fs ALIGN=MIDDLE  ALT=\"40%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13%2F60 ALIGN=MIDDLE  ALT=\"13%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" >; <BR>\n" );
document.write( "mult by 60s, results<BR>\n" );
document.write( "2s(40) - 60(40) = 13s<BR>\n" );
document.write( "80s - 2400 = 13s<BR>\n" );
document.write( "80s - 13s = 240<BR>\n" );
document.write( "67s = 2400<BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2400%2F67 ALIGN=MIDDLE  ALT=\"2400%2F67\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 35.82 mph the ideal speed<BR>\n" );
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document.write( "Check solution in the late equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2F30 ALIGN=MIDDLE  ALT=\"40%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40%2F35.82 ALIGN=MIDDLE  ALT=\"40%2F35.82\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <BR>\n" );
document.write( "1.3333 - 1.1167 = .2166 hr which is 13 min </SPAN>\n" );
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