document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1193272>Question 1193272</A>: <I><SPAN STYLE=\"word-break: break-all;\"> MAT 145: Topics In Contemporary Math\r<BR>\n" );
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document.write( "             19: Solving Exponential Growth\r<BR>\n" );
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document.write( "4) The population of bison was almost hunted to extinction when the United States <BR>\n" );
document.write( "expanded westward. The population decreased by 40% per year when the expansion <BR>\n" );
document.write( "began in 1803. If the herds of bison originally contained 500,000 bison, long would it <BR>\n" );
document.write( "take for there to only be 1,000 bison left? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #825277 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=825277\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The population of bison was almost hunted to extinction when the United States<BR>\n" );
document.write( "expanded westward.<BR>\n" );
document.write( " The population decreased by 40% per year when the expansion began in 1803.<BR>\n" );
document.write( " If the herds of bison originally contained 500,000 bison, long would it<BR>\n" );
document.write( "take for there to only be 1,000 bison left? <BR>\n" );
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document.write( "let t = time required for this to happen<BR>\n" );
document.write( "With 40% decrease, that means .6 of original amt remain<BR>\n" );
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document.write( "500000*.6^t = 1000<BR>\n" );
document.write( ".6^t = 1000/500000<BR>\n" );
document.write( ".6^t = 1/500<BR>\n" );
document.write( "uing natural logs<BR>\n" );
document.write( "t*ln(.6) = ln(1/500)<BR>\n" );
document.write( "t = ln(1/500)/ln(.6)<BR>\n" );
document.write( "using calc<BR>\n" );
document.write( "t ~ 12 years </SPAN>\n" );
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