document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=207642>Question 207642</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534404693/algebrahomeworkh>Algebra and Trigonometry with Analytic Geometry</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Can you please solve question (b) for me? Here's the problem:\r<BR>\n" );
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document.write( "Below the cloud base, the temperature T (in F) at heigh h (in feet) can be approximated by the equation T=To - (5.5/1000)h, where To is the temperature at ground level. (a) Determine the air temperature at a height of 1 mile if the ground temperature is 70 degrees F. (b) At what altitude is the temperature freezing.  \r<BR>\n" );
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document.write( "I'm not sure what number to plug in for \"T\", but the answer is 6909 feet.  Thank you for any help! :)<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #157044 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=157044\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> T[0] = temperature at ground level = 70 degrees.<BR>\n" );
document.write( "formula is T[0] - (5.5/1000)*h<BR>\n" );
document.write( "I am presuming h is in feet since the answer you gave is 6909 feet.<BR>\n" );
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document.write( "1 mile is 5280 feet.<BR>\n" );
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document.write( "temperature 1 miles up should be 70 - (5.5/1000)*5280 = 40.96 degrees.<BR>\n" );
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document.write( "since freezing is 32 degrees (fahrenheit<BR>\n" );
document.write( "70 - (5.5/1000)*h = 32<BR>\n" );
document.write( "solving for h we:<BR>\n" );
document.write( "subtract 32 from both sides of the equation to get:<BR>\n" );
document.write( "70 - 32 = 5.5/1000*h <BR>\n" );
document.write( "simplifying we get:<BR>\n" );
document.write( "38 = 5.5/1000*h<BR>\n" );
document.write( "we multiply both sides of the equation by 1000/5.5 to get:<BR>\n" );
document.write( "38*1000/5.5 = h<BR>\n" );
document.write( "we simplify to get:<BR>\n" );
document.write( "h = 38*1000/5.5 = 6909.090909 = 6909 rounded to the nearest integer.<BR>\n" );
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document.write( "looks like 6909 was the right number.<BR>\n" );
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