document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=237530>Question 237530</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello. I seem to have particular trouble with word problems. I can't develop the equation so I never get to the point of solving it. Each time I do it correctly, it seems like a fluke and I can't recreate it. I'd appreciate any help you can offer. \r<BR>\n" );
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document.write( "Here is the question:<BR>\n" );
document.write( "Suppose that Car A can travel 250 miles in 3 hours less time than it takes Car B to travel 440 miles. The rate of Car B is 5 miles per hour faster than that of Car A. Find the rates of both cars.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #174682 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=174682\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You picked a tough problem but we can do it.<BR>\n" );
document.write( "a) what formula are you going to use? Ans.: st=d,  speed * time=distance<BR>\n" );
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document.write( "b) speed<BR>\n" );
document.write( "Let s-5=car A's speed<BR>\n" );
document.write( "Let s=car B's speed<BR>\n" );
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document.write( "c)time<BR>\n" );
document.write( "Let t=car B's time<BR>\n" );
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document.write( "We can make a system of equations now. Look at the formula for B 1st because it is the simplest.<BR>\n" );
document.write( "A) (s-5)(t-3)=250<BR>\n" );
document.write( "B) st=440<BR>\n" );
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document.write( "B) s=440/t<BR>\n" );
document.write( "A) <BR>\n" );
document.write( "(440/t -5)(t-3)=250 Substitute 440/t for s<BR>\n" );
document.write( "(440-5t)(t-3)=250t multiply t times each side to eliminate the fraction.<BR>\n" );
document.write( "-5t^2+455t-1320=250t<BR>\n" );
document.write( "t^2-91t+264=-50t Divide each side by -5<BR>\n" );
document.write( "t^2-41t+264=0<BR>\n" );
document.write( "(t-8)(t-33)=0 Factor<BR>\n" );
document.write( "t=8 hrs, t=33 hrs<BR>\n" );
document.write( "If we use t=8 then for B: s=440/8=55mph<BR>\n" );
document.write( "Then for A: s=50mph<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "A travels 250 mi in 5h<BR>\n" );
document.write( "B travels 440 mi in 8h which is 3hrs longer than A traveling 250mi.<BR>\n" );
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document.write( "Ed\r<BR>\n" );
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document.write( ". </SPAN>\n" );
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