document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=620145>Question 620145</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello, I need help in solving this problem:\r<BR>\n" );
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document.write( "A plane flew 150 kilometers with a 30 km/hr tailwind, then turned into the wind<BR>\n" );
document.write( "and flew for another 65 kilometers. If the wind and the plane’s airspeed were<BR>\n" );
document.write( "constant and the entire trip took 30 minutes, what was the plane’s airspeed?<BR>\n" );
document.write( "(Ignore the time needed to turn the plane around).\r<BR>\n" );
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document.write( "Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #389966 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10552)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=389966\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "Hello, I need help in solving this problem:\r<BR>\n" );
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document.write( "A plane flew 150 kilometers with a 30 km/hr tailwind, then turned into the wind<BR>\n" );
document.write( "and flew for another 65 kilometers. If the wind and the plane’s airspeed were<BR>\n" );
document.write( "constant and the entire trip took 30 minutes, what was the plane’s airspeed?<BR>\n" );
document.write( "(Ignore the time needed to turn the plane around).\r<BR>\n" );
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document.write( "Thank you.\r<BR>\n" );
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document.write( "Let speed of plane in still air be S<BR>\n" );
document.write( "Time taken to travel 150 km, plus time taken to fly 65 km, equals entire time taken (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F60 ALIGN=MIDDLE  ALT=\"30%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or ˝ hour)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150%2F%28S+%2B+30%29+%2B+65%2F%28S+-+30%29+=+%281%2F2%29 ALIGN=MIDDLE  ALT=\"150%2F%28S+%2B+30%29+%2B+65%2F%28S+-+30%29+=+%281%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "300(S - 30) + 130(S + 30) = (S + 30)(S - 30) ------ Multiplying by LCD, 2(S + 30)(S – 30)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=300S+-+9000+%2B+130S+%2B+3900+=+S%5E2+-+900 ALIGN=MIDDLE  ALT=\"300S+-+9000+%2B+130S+%2B+3900+=+S%5E2+-+900\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=430S+-+5100+=+S%5E2+-+900 ALIGN=MIDDLE  ALT=\"430S+-+5100+=+S%5E2+-+900\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5E2+-+430S+-+900+%2B+5100+=+0 ALIGN=MIDDLE  ALT=\"S%5E2+-+430S+-+900+%2B+5100+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%5E2+-+430S+%2B+4200+=+0 ALIGN=MIDDLE  ALT=\"S%5E2+-+430S+%2B+4200+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "(S - 10)(S - 420) = 0\r<BR>\n" );
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document.write( "S, or speed in still air = 10 (ignore as this is IMPOSSIBLE, because the wind speed CANNOT EXCEED the plane’s speed), OR\r<BR>\n" );
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document.write( "S, or speed of plane in still air = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28420%29 ALIGN=MIDDLE  ALT=\"highlight_green%28420%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > km/h \r<BR>\n" );
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document.write( "I’ll leave the check up to you.\r<BR>\n" );
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document.write( "Send comments and “thank-yous” to “D” at  MathMadEzy@aol.com </SPAN>\n" );
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