document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=713101>Question 713101</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The altitude of an aircraft, h, in miles, is given by<BR>\n" );
document.write( "h= - (100/9)log p/b\r<BR>\n" );
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document.write( "where P = the outside pressure and B = the atmospheric pressure at sea level. Let B = 31 inches of mercury. What is the outside air pressure at a height of 2.7 miles? Round your answer to the nearest tenth.<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 #438292 by </B><A HREF=/tutors/aboutme.mpl?userid=jsmallt9><B>jsmallt9(3758)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jsmallt9><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=438292\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=+-+%28100%2F9%29log%28%28p%2Fb%29%29 ALIGN=MIDDLE  ALT=\"h=+-+%28100%2F9%29log%28%28p%2Fb%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substituting in the values given for b and h we get:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2.7+=+-%28100%2F9%29log%28%28p%2F31%29%29 ALIGN=MIDDLE  ALT=\"2.7+=+-%28100%2F9%29log%28%28p%2F31%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "And now we solve for p. First we'll isolate the log. Multiplying both sides by -9/100:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-9%2F100%29%2A%282.7%29+=+%28-9%2F100%29%2A%28-%28100%2F9%29log%28%28p%2F31%29%29%29 ALIGN=MIDDLE  ALT=\"%28-9%2F100%29%2A%282.7%29+=+%28-9%2F100%29%2A%28-%28100%2F9%29log%28%28p%2F31%29%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-.243+=+log%28%28p%2F31%29%29 ALIGN=MIDDLE  ALT=\"-.243+=+log%28%28p%2F31%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Next we rewrite the equation in exponential form. In general <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%28a%2C+%28p%29%29+=+n ALIGN=MIDDLE  ALT=\"log%28a%2C+%28p%29%29+=+n\"   DISABLED_style= \"max-width:90%; height:auto;\" > is equivalent to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p+=+a%5En ALIGN=MIDDLE  ALT=\"p+=+a%5En\"   DISABLED_style= \"max-width:90%; height:auto;\" >. Using this pattern (and the fact that the base of \"log\" is 10) on our equation we get:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%5E%28-.243%29+=+p%2F31 ALIGN=MIDDLE  ALT=\"10%5E%28-.243%29+=+p%2F31\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Next we multiply both sides by 31:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=31%2A10%5E%28-.243%29+=+p ALIGN=MIDDLE  ALT=\"31%2A10%5E%28-.243%29+=+p\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "This is an exact expression for the solution. I'll leave it up to you to use your calculator to find the decimal. (Just be sure to raise 10 to the -.243 power before you multiply by 31.)<BR>\n" );
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