document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=603093>Question 603093</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi Dear Tutor I need your help to explain to me how we put this word problem into a equation. I tried here but i dont think i m getting the right answer, plus my book does not have a similiar example. You dont have to give me the answer but if you could show me how to make the equation with this information. \r<BR>\n" );
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document.write( "Thank You very much,\r<BR>\n" );
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document.write( "Monick\r<BR>\n" );
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document.write( "1)A plane traveled 630 miles to Tokyo and back. The trip there was with the wind.It took 7 hours. The trip back was into the wind. The trip back took 21 hours. What is the speed of a plane in still air? what is the speed 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 #380574 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=380574\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1)A plane traveled 630 miles to Tokyo and back. The trip there was with the wind.It took 7 hours. The trip back was into the wind. The trip back took 21 hours. What is the speed of a plane in still air? what is the speed of the wind?<BR>\n" );
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document.write( "let x=speed of plane in still air<BR>\n" );
document.write( "let c=speed of wind<BR>\n" );
document.write( "(x+c)=net speed of plane with wind<BR>\n" );
document.write( "(x-c)=net speed of plane into wind<BR>\n" );
document.write( "distance=travel time*speed<BR>\n" );
document.write( "..<BR>\n" );
document.write( "7(x+c)=630<BR>\n" );
document.write( "21(x-c)=630<BR>\n" );
document.write( "..<BR>\n" );
document.write( "7x+7c=630<BR>\n" );
document.write( "21x-21c=630<BR>\n" );
document.write( "..<BR>\n" );
document.write( "21x+21c=1890<BR>\n" );
document.write( "21x-21c=630<BR>\n" );
document.write( "add, eliminating c<BR>\n" );
document.write( "42x=2520<BR>\n" );
document.write( "x=2520/70=60<BR>\n" );
document.write( "7c=630-7x=630-420=210<BR>\n" );
document.write( "c=30<BR>\n" );
document.write( "..<BR>\n" );
document.write( "ans:<BR>\n" );
document.write( "speed of plane in still air=60 mph <BR>\n" );
document.write( "speed of wind=30 mph<BR>\n" );
document.write( "..<BR>\n" );
document.write( "50 mph for plane speed seems a bit slow for this type of problem\r<BR>\n" );
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document.write( " </SPAN>\n" );
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