document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=78708>Question 78708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do u solve this question?\r<BR>\n" );
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document.write( "A study monitored the life spans of 129 robins over 4 years.  The equation   was developed to calculate the number of years y for x percent of the robin population to die.<BR>\n" );
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document.write( "y= 2-log(100-x)/.42\r<BR>\n" );
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document.write( "How many robins had died after 6 months?<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 #56453 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=56453\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A study monitored the life spans of 129 robins over 4 years. The equation was developed to calculate the number of years y for x percent of the robin population to die.\r<BR>\n" );
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document.write( "y= 2-log(100-x)/.42<BR>\n" );
document.write( "How many robins had died after 6 months?<BR>\n" );
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document.write( "6 months = .5 years<BR>\n" );
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document.write( "(2 - log(100-x))/.42 = .5<BR>\n" );
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document.write( "2 - log(100-x) = .5 * .42; multiplied both sides by .42<BR>\n" );
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document.write( "2 - log(100-x) = .21<BR>\n" );
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document.write( "- log(100-x) = .21 - 2<BR>\n" );
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document.write( "- log(100-x) = -1.79<BR>\n" );
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document.write( "log(100-x) = 1.79; multiplied equation by -1<BR>\n" );
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document.write( "Find the anti-log (10^x) of both sides:<BR>\n" );
document.write( "100 - x = 61.66 <BR>\n" );
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document.write( "-x = 61.66 - 100<BR>\n" );
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document.write( "-x = -38.34; (*-1)<BR>\n" );
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document.write( "x = +38.34%; Therefore, .3834 * 129 = 49 birdies bit the dust in 6 mos<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "y = (2-log(100-38.34))/.42<BR>\n" );
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document.write( "y = (2 - log(61.66))/.42<BR>\n" );
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document.write( "y = (2 - 1.79)/.42<BR>\n" );
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document.write( "y = .4999 ~ .5  </SPAN>\n" );
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