document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=174973>Question 174973</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help!!<BR>\n" );
document.write( "- A car travelled 470 km from Sudbury to Brandford in 5 hours. For part of the trip, the car travelled at 100 km/h. For the rest of the trip, it travelled at 90 km/h. How far did the car travel at each speed?\r<BR>\n" );
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document.write( "I tried <BR>\n" );
document.write( "x+y=5<BR>\n" );
document.write( "100x+90=470\r<BR>\n" );
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document.write( "100x+100y=500<BR>\n" );
document.write( "100x+90y=470\r<BR>\n" );
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document.write( "= 10y = 30<BR>\n" );
document.write( "x=2 y=3<BR>\n" );
document.write( "but I only got half marks. Where did I go wrong and what was the answer? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #130043 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=130043\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A car travelled 470 km from Sudbury to Brandford in 5 hours. For part of the trip, the car traveled at 100 km/h. For the rest of the trip it traveled at 90 km/h. How far did the car travel at each speed? <BR>\n" );
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document.write( "100 kph section DATA:<BR>\n" );
document.write( "Distance = x km ; rate = 100 kph ; time = d/r = x/100 hrs.<BR>\n" );
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document.write( "90 kph section DATA:<BR>\n" );
document.write( "Distance = 470 - x km ; rate = 90 kph ; time = d/r = (470-x)/90 hrs<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "time + time = 5 hrs<BR>\n" );
document.write( "x/100 + (470-x)/90 = 5<BR>\n" );
document.write( "90x + 100(470-x) = 450*100<BR>\n" );
document.write( "90x + 100*470 - 100x = 450*100<BR>\n" );
document.write( "-10x = -20*100<BR>\n" );
document.write( "x = 200 km (distance traveled at 100 kph)<BR>\n" );
document.write( "470-x = 270 km (distance traveled at 90 kph)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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