document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=332548>Question 332548</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A turboprop plane flying with the wind flew 1,400 mi in 5 h. Flying against the wind, the plane required 7 h to travel the same distance. Find the rate of the wind and the rate of the plane in calm air. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #238331 by </B><A HREF=/tutors/aboutme.mpl?userid=galactus><B>galactus(183)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=galactus><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=galactus><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=238331\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> With the wind, we add the two rates. Against the wind, we subtract them.\r<BR>\n" );
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document.write( "Let rp=rate of plane and rw = the rate of thr wind.\r<BR>\n" );
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document.write( "With the wind:\r<BR>\n" );
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document.write( "Since d=rt, we have 1400=5(rp+rw)\r<BR>\n" );
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document.write( "Against the wind:\r<BR>\n" );
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document.write( "we have 1400=7(rp-rw)\r<BR>\n" );
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document.write( "These reduce to \r<BR>\n" );
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document.write( "rp+rw=280<BR>\n" );
document.write( "rp-rw=200\r<BR>\n" );
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document.write( "Now, from the first equation we have rp=280-rw\r<BR>\n" );
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document.write( "Sub into the second equation:\r<BR>\n" );
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document.write( "280-rw-rw=200\r<BR>\n" );
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document.write( "280-2rw=200\r<BR>\n" );
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document.write( "rw=40=rate of wind.\r<BR>\n" );
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document.write( "That means the rate of the plane, rp, is 240.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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