document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=203473>Question 203473</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780073533490/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Big plane. A six-passenger plane cruises at 180 mph in<BR>\n" );
document.write( "calm air. If the plane flies 7 miles with the wind in the<BR>\n" );
document.write( "same amount of time as it flies 5 miles against the wind,<BR>\n" );
document.write( "then what is the wind speed? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #153507 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=153507\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A six-passenger plane cruises at 180 mph in calm air.<BR>\n" );
document.write( " If the plane flies 7 miles with the wind in the same amount of time<BR>\n" );
document.write( " as it flies 5 miles against the wind, then what is the wind speed?<BR>\n" );
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document.write( "Let w = speed of the wind<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(180+w) = plane speed with the wind<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(180-w) = plane speed against the wind<BR>\n" );
document.write( ":<BR>\n" );
document.write( "The time of the two trips is equal, write a time equation<BR>\n" );
document.write( "Time = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dist%2Fspeed ALIGN=MIDDLE  ALT=\"dist%2Fspeed\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "7 mi time = 5 mi time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2F%28%28180%2Bw%29%29 ALIGN=MIDDLE  ALT=\"7%2F%28%28180%2Bw%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F%28%28180-w%29%29 ALIGN=MIDDLE  ALT=\"5%2F%28%28180-w%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Cross multiply<BR>\n" );
document.write( "7(180-w) = 5(180+w)<BR>\n" );
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document.write( "1260 - 7w = 900 + 5w<BR>\n" );
document.write( ":<BR>\n" );
document.write( "1260 - 900 = 5w + 7w<BR>\n" );
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document.write( "360 = 12w<BR>\n" );
document.write( "w = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=360%2F12 ALIGN=MIDDLE  ALT=\"360%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "w = 30 mph is the speed of the wind<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check solution by finding the times, are they equal(210 with, 150 against)<BR>\n" );
document.write( "7/210 = .033<BR>\n" );
document.write( "5/150 = .033 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );