document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=485900>Question 485900</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how fast would speed have to travel to cover half the earth in 14.7 hours </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #332270 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=332270\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the circumference of the earth at the equator is 24,900 miles +/- 1 or 2.<BR>\n" );
document.write( "if you want to travel in an airplane, and the airplane is traveling at 7 miles above the earth (that's about 36960 feet), then the distance to circumnavigate the globe would be a little longer.\r<BR>\n" );
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document.write( "if the circumference is 24,900 miles, then the radius is 3962.958083 miles.<BR>\n" );
document.write( "add 7 to that and you get a radius of 3969.958083 miles.\r<BR>\n" );
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document.write( "the circumference of the earth at that altitude is equal to 2 * pi * 3969.958083 miles which is equal to 24,943.9823 miles.\r<BR>\n" );
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document.write( "we're not talking a big difference, but there is a difference.<BR>\n" );
document.write( "circumference on the surface of the earth is 24,900 miles.<BR>\n" );
document.write( "circumference at 7 miles above the surface of the earthy is 24,943.9823 miles.\r<BR>\n" );
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document.write( "this is definitely not a big deal (it's only 43 miles) and we can ignore it for practical purposes, so we will.\r<BR>\n" );
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document.write( "the circumference of the earth at the equator is 24,900 miles.\r<BR>\n" );
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document.write( "you want to travel half the distance in 14.7 hours.\r<BR>\n" );
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document.write( "half the distance is 12,450 miles.\r<BR>\n" );
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document.write( "12,450 / 14.7 = 846.9387755 miles per hour.\r<BR>\n" );
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document.write( "that's roughly 847 miles per hour.\r<BR>\n" );
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document.write( "that's the speed you would have to travel at.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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