document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1069142>Question 1069142</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A train averages a speed of 90 miles per hour across the plains and 37.5 miles per hour through the mountains. If a trip of 300 miles took 3 hour and 48 minutes, how much of it was through the mountains? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #684371 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=684371\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A train averages a speed of 90 miles per hour across the plains and 37.5 miles per hour through the mountains.<BR>\n" );
document.write( " If a trip of 300 miles took 3 hour and 48 minutes, how much of it was through the mountains?<BR>\n" );
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document.write( "Let d = distance traveled at 37.5 (thru the mountains)<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(300-d) = distance traveled at 90 mph<BR>\n" );
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document.write( "Write a time equation, time = dist/speed<BR>\n" );
document.write( "change 3 hr 48 min to hrs: 3 + 48/60 = 3.8 hrs<BR>\n" );
document.write( "plain time + mountain time = 3.8 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28300-d%29%2F90 ALIGN=MIDDLE  ALT=\"%28300-d%29%2F90\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F37.5 ALIGN=MIDDLE  ALT=\"d%2F37.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 3.8<BR>\n" );
document.write( "Multiply 90*37.5<BR>\n" );
document.write( "3375*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28300-d%29%2F90 ALIGN=MIDDLE  ALT=\"%28300-d%29%2F90\"   DISABLED_style= \"max-width:90%; height:auto;\" > + 3375*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F37.5 ALIGN=MIDDLE  ALT=\"d%2F37.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 3.8(3375)<BR>\n" );
document.write( "cancel the denominator<BR>\n" );
document.write( "37.5(300-d) + 90d = 12825<BR>\n" );
document.write( "11250 - 37.5d + 90d = 12825<BR>\n" );
document.write( "52.5d = 1575<BR>\n" );
document.write( "d = 1575/52.5<BR>\n" );
document.write( "d = 30 mi thru the mountains<BR>\n" );
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document.write( ";<BR>\n" );
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document.write( "Check this, find the distance on the plain<BR>\n" );
document.write( "300-30 = 270 mi<BR>\n" );
document.write( "Find the actual time at each speed<BR>\n" );
document.write( "270/90 = 3 hrs<BR>\n" );
document.write( "30/37.5 = .8 hrs<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "total time: 3.8 hrs\r<BR>\n" );
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document.write( "  </SPAN>\n" );
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