document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=920756>Question 920756</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this question: In 2hours 30 minutes an airplane travels 600 km against the wind. The return trip (with the wind) takes 1 hour 40 minutes. Find the speed of the wind and the speed of the airplane in still air.\r<BR>\n" );
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document.write( "I used D=RT plugging in 600 and 150 (2hr30min) and the answers aren't matching up with the answers on the sheet.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #558582 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=558582\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In 2hours 30 minutes an airplane travels 600 km against the wind.<BR>\n" );
document.write( " The return trip (with the wind) takes 1 hour 40 minutes.<BR>\n" );
document.write( " Find the speed of the wind and the speed of the airplane in still air.<BR>\n" );
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document.write( "Since we are dealing in km/hr, Convert the given times to hrs<BR>\n" );
document.write( "2 hr 30 min = 2.5 hrs<BR>\n" );
document.write( "1 hr 40 min = 1<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3 ALIGN=MIDDLE  ALT=\"2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs (40/60)<BR>\n" );
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document.write( "let s = speed in still air<BR>\n" );
document.write( "let w = speed of the wind<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+c) = speed with the wind<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s-c) = speed against the wind<BR>\n" );
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document.write( "Write a distance equation for each way<BR>\n" );
document.write( "2.5(s - c) = 600<BR>\n" );
document.write( "1<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3 ALIGN=MIDDLE  ALT=\"2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >(s + c) = 600<BR>\n" );
document.write( "we can greatly simplify these equations, divide the 1st by 2.5 the 2nd by 1<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3 ALIGN=MIDDLE  ALT=\"2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > and we have<BR>\n" );
document.write( "s - c = 240<BR>\n" );
document.write( "s + c = 360<BR>\n" );
document.write( "--------------adding eliminates c, find s<BR>\n" );
document.write( "2s = 600<BR>\n" );
document.write( "s = 300 km/hr in still air<BR>\n" );
document.write( "find w<BR>\n" );
document.write( "300 + c = 360<BR>\n" );
document.write( "c = 60 km/hr is the speed of the wind<BR>\n" );
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document.write( "Check these solutions in the original equations </SPAN>\n" );
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