document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=667753>Question 667753</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The speed of  a plane is 120 miles/hour in a calm. With the wind it can cover a certain distance in 4 hours, but against the wind it can cover only 3/5 of that distance in the same time. Find the velocity of the wind. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #415147 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=415147\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> velocity of wind = x mi/h<BR>\n" );
document.write( "with wind speed  of plane = 120 +x mi/h\r<BR>\n" );
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document.write( "D1= (120+x)*4\r<BR>\n" );
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document.write( "against wind speed = 120-x mi/h<BR>\n" );
document.write( "D2= (120-x)*4\r<BR>\n" );
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document.write( "D2= 3/5 D1\r<BR>\n" );
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document.write( "3/5(120+x)*4 = (120-x)*4\r<BR>\n" );
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document.write( "3(120+x)=5(120-x)<BR>\n" );
document.write( "360+3x=600-5x<BR>\n" );
document.write( "8x= 240<BR>\n" );
document.write( "x=30\r<BR>\n" );
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document.write( "wind speed = 30 mi/h </SPAN>\n" );
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