document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=669703>Question 669703</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, I would like to know if someone can help with this word problem? thanks. \r<BR>\n" );
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document.write( "Jeff starts driving at 55mph from the same point that Lauren starts driving at 70mph. They drive in opposite directions, and Lauren has a half-hour head start. How long will they be able to talk on their cell phones that have a 440 mile range?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #416538 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=416538\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if i did this correctly, they should be able to talk for 3.74 hours.<BR>\n" );
document.write( "first of all, lauren drives for 1/2 hour before jeff starts.<BR>\n" );
document.write( "70 mph for 1/3 hour is equal to 35 miles.<BR>\n" );
document.write( "then jeff starts.<BR>\n" );
document.write( "once jess starts, they will both be driving for the same time.<BR>\n" );
document.write( "the total distance they need to travel to be 440 miles apart is now only an additional 405 miles since lauren is already 35 miles away.<BR>\n" );
document.write( "the formula is rate * time  = distance.<BR>\n" );
document.write( "the distance that jeff travels is equal to his rate * the mutual time which is called T.<BR>\n" );
document.write( "his distance is therefore 55T<BR>\n" );
document.write( "lauren's distance is therefore 70T<BR>\n" );
document.write( "the total distance traveled by both has to equal 440 miles minus 35 miles = 405 miles.<BR>\n" );
document.write( "the formula becomes 55T + 70T = 405<BR>\n" );
document.write( "solve for T to get T = 3.24 hours.<BR>\n" );
document.write( "you have to add the 1/2 hours that lauren was driving while jeff was just sitting there to get a total of 3.74 hours where they can still be in touch with each other.<BR>\n" );
document.write( "after that, they're out of range.<BR>\n" );
document.write( "the breakdown is as follows:<BR>\n" );
document.write( "lauren drives for 35 miles before jeff even starts.<BR>\n" );
document.write( "jeff drives at 55 miles per hour for 3.24 hours for a distance of 178.2 miles<BR>\n" );
document.write( "lauren drives at 70 miles per hour for the same 3.24 hours for a distance of 226.8 miles.<BR>\n" );
document.write( "jeff has gone 178.2 miles in one direction.<BR>\n" );
document.write( "lauren has gone 226.8 + 35 = 261.8 miles in the other direction.<BR>\n" );
document.write( "the total distance between them is 178.2 + 261.8 = 440 miles.\r<BR>\n" );
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document.write( "the answer to the question is that they will be able to talk on their cell phones for a total of 3.74 hours.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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