document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=944356>Question 944356</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In the first half (distance) of a trip, a truck travels at a speed of 40 km/hr. How fast must it go during the second half of the trip to average 50 km/hr for the entire trip?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #575802 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=575802\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In the first half (distance) of a trip, a truck travels at a speed of 40 km/hr.<BR>\n" );
document.write( " How fast must it go during the second half of the trip to average 50 km/hr for the entire trip?<BR>\n" );
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document.write( "Let s = speed required on the 2nd half to average 50 km/hr<BR>\n" );
document.write( "let d = half the distance of the trip<BR>\n" );
document.write( "Write time equation; time = dist/speed<BR>\n" );
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document.write( "1st half time + 2nd half time = total time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F40%29 ALIGN=MIDDLE  ALT=\"d%2F40%29\"   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=%282d%29%2F50 ALIGN=MIDDLE  ALT=\"%282d%29%2F50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "multiply equation by 200s<BR>\n" );
document.write( "200s*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F40%29 ALIGN=MIDDLE  ALT=\"d%2F40%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + 200s*<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;\" > = 200s*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282d%29%2F50 ALIGN=MIDDLE  ALT=\"%282d%29%2F50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "cancel the denominators and you have<BR>\n" );
document.write( "5ds + 200d = 4s(2d)<BR>\n" );
document.write( "5ds + 200d = 8ds<BR>\n" );
document.write( "Get rid of d, divide thru by d<BR>\n" );
document.write( "5s + 200 = 8s<BR>\n" );
document.write( "200 = 8s - 5s<BR>\n" );
document.write( "200 = 3s<BR>\n" );
document.write( "s = 200/3<BR>\n" );
document.write( "s = 66.67 km/h on the 2nd half of the trip <BR>\n" );
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document.write( "We can confirm this by choosing a distance (200 km half-way) and substituting for s, find the times<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=200%2F40%29 ALIGN=MIDDLE  ALT=\"200%2F40%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=200%2F66.67 ALIGN=MIDDLE  ALT=\"200%2F66.67\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=400%2F50 ALIGN=MIDDLE  ALT=\"400%2F50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "5 hrs + 3 hrs = 8 hrs<BR>\n" );
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