document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=115726>Question 115726</A>: <I><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "A plane flies 720 miles against a steady 30mi/h headwind and then returns to the same point with the wind.  If the entire trip takes 10 hrs, what is the plane's speed in still air?\r<BR>\n" );
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document.write( "720/30 = 10/x<BR>\n" );
document.write( "720x = 30*10<BR>\n" );
document.write( "720x = 300<BR>\n" );
document.write( "720x/720 = 300/720\r<BR>\n" );
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document.write( "Am I on the right track on solving this problem because the answer I come up with is not a whole number? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #84304 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley71><B>checkley71(8403)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley71><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=84304\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> D=RT <BR>\n" );
document.write( "T=D/R<BR>\n" );
document.write( "10=720/(R-30)+720/(R+30) COMBINE THE FRACTIONS USING THE COMMON DENOMINATOR:<BR>\n" );
document.write( "(R-30)(R+30) <BR>\n" );
document.write( "10=[720(R+30)+720(R-30)]/(R-30)(R+30)<BR>\n" );
document.write( "10=(720R+21600+720R-21600)/(R^2-900)<BR>\n" );
document.write( "10=1440R/(R^2-900) CROSS MULTIPLY<BR>\n" );
document.write( "10(R^2-900)=1440R<BR>\n" );
document.write( "10R^2-1440R-9000=0<BR>\n" );
document.write( "10(R^2-144R-900)=0<BR>\n" );
document.write( "10(R-150)(R+6)=0<BR>\n" );
document.write( "5-150=0<BR>\n" );
document.write( "R=150 ANSWER FOR THE SPEED OF THE AIRPLANE.<BR>\n" );
document.write( "PROOF<BR>\n" );
document.write( "10=720/(150-30)+720/(150+30)<BR>\n" );
document.write( "10=720/180+720/120 <BR>\n" );
document.write( "10=4+6<BR>\n" );
document.write( "10=10<BR>\n" );
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