document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=158839>Question 158839</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi I am a granfather of 75 yrs old. trying to help out his grandaughter. she has been working on a algebra problem for hours finish all but one question. Sent her home with her mother who tried also.she was so tired I sent her to bed. Its been 60 yrs since I had to do math..lol She just doesn't understand how to begin..Honestly we tried. if you can help it would be wonderful. the question is <BR>\n" );
document.write( "two trains traveling in different directions one at 55mph and the other at 45mph<BR>\n" );
document.write( "they traveled a total of 400 miles how long did it take to go that distance...<BR>\n" );
document.write( "she doesn't know how to work out the formula...rate and time. thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #116981 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=116981\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> two trains traveling in different directions one at 55mph and the other at 45mph<BR>\n" );
document.write( "they traveled a total of 400 miles how long did it take to go that distance...<BR>\n" );
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document.write( "The basic formula is: distance = rate * time<BR>\n" );
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document.write( "1st train DATA:<BR>\n" );
document.write( "rate = 55 mph ; distance = x miles ; time = d/r = x/55 hrs.<BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "2nd train DATA:<BR>\n" );
document.write( "rate = 45 mph ; distance = (400-x) miles ; time = d/r = (400-x)/45 hrs<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "time = time<BR>\n" );
document.write( "x/55 = (400-x)/45<BR>\n" );
document.write( "Cross-multiply to get:<BR>\n" );
document.write( "45x = 55(400-x)<BR>\n" );
document.write( "45x = 55*400 - 55x<BR>\n" );
document.write( "100x = 55*400<BR>\n" );
document.write( "x = 55*4<BR>\n" );
document.write( "x = 220 miles<BR>\n" );
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document.write( "time = distance/rate<BR>\n" );
document.write( "time = 220 / 55 = 4 hours <BR>\n" );
document.write( "The time is the same for both of the trains.<BR>\n" );
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document.write( "Another way to do the problem.<BR>\n" );
document.write( "The trains are going away from one another at (45+55) = 100 mph<BR>\n" );
document.write( "The time for them to be 400 miles apart is 400/100 = 4 hours.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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