document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=759942>Question 759942</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A truck heads north at a constant speed of 80 km/h. A car leaves 20 minutes <BR>\n" );
document.write( "later heading north along the same road and travelling at a constant speed of <BR>\n" );
document.write( "90 km/h.<BR>\n" );
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document.write( "Write an equation that could be used to determine how much time in <BR>\n" );
document.write( "hours, t, the car travels until it catches up to the truck. \r<BR>\n" );
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document.write( "**The correct answer is 90t = 80(t+1/3) , but I need help understanding why**  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #462376 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10552)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=462376\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "A truck heads north at a constant speed of 80 km/h. A car leaves 20 minutes <BR>\n" );
document.write( "later heading north along the same road and travelling at a constant speed of <BR>\n" );
document.write( "90 km/h.<BR>\n" );
document.write( " <BR>\n" );
document.write( "Write an equation that could be used to determine how much time in <BR>\n" );
document.write( "hours, t, the car travels until it catches up to the truck. \r<BR>\n" );
document.write( "\n" );
document.write( "**The correct answer is 90t = 80(t+1/3) , but I need help understanding why** \r<BR>\n" );
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document.write( "Let time it takes car to catch up to truck (get to meeting point) be T\r<BR>\n" );
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document.write( "Then time it'll take truck to get to meeting point = T + 1/3, since the truck will take a longer time to get to the meeting point as it's traveling at a slower speed\r<BR>\n" );
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document.write( "Distance car travels to get to meeting point = 90(T), or 90T\r<BR>\n" );
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document.write( "Distance truck travels to get to meeting point = 80(T + 1/3)\r<BR>\n" );
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document.write( "Both vehicles would've traveled the same distance, so: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%2890T+=+80%28T+%2B+1%2F3%29%29 ALIGN=MIDDLE  ALT=\"highlight_green%2890T+=+80%28T+%2B+1%2F3%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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