document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=903540>Question 903540</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1.) A jet plane, flying 120 mph faster than a propeller plane, travels 5760 miles in 4 hours less time than the propeller plane takes to fly the same distance. How fast does each plane fly?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #548128 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=548128\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1.) A jet plane, flying 120 mph faster than a propeller plane, travels 5760 miles in 4 hours less time than the propeller plane takes to fly the same distance. How fast does each plane fly?<BR>\n" );
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document.write( "Prop distance:: r(t+4)<BR>\n" );
document.write( "Jet distance:: (r+120)t<BR>\n" );
document.write( "rt+4r = rt + 120t<BR>\n" );
document.write( "r = 30t<BR>\n" );
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document.write( "Jet DATA:<BR>\n" );
document.write( "distance = 5760 miles ; rate = x+120 mph ; time = d/r = 5760/(x+120)<BR>\n" );
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document.write( "Prop DATA::<BR>\n" );
document.write( "distnce = 5760 miles ; rate = x mph ; time = d/r = 5760/x<BR>\n" );
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document.write( "Equation::<BR>\n" );
document.write( "time - time = 4<BR>\n" );
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document.write( "prop time - jet time = 4 hrs<BR>\n" );
document.write( "5760/x - 5760/(x+120) = 4<BR>\n" );
document.write( "120*5760 = 4x(x+120)<BR>\n" );
document.write( "30*5760 = x^2 + 120x<BR>\n" );
document.write( "x^2+120x-30*5760 = 0<BR>\n" );
document.write( "(x-360)(x+480) = 0<BR>\n" );
document.write( "Positive solution::<BR>\n" );
document.write( "x = 360 mph (prop plane speed)<BR>\n" );
document.write( "x+120 = 480 mph (jet plane speed)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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