document.write( "Question 585462: The population of fish in a lake is decreasing. There are currently 24,000 fish in the lake. The population is decreasing 6% each year. In how many years will there be 1/4 of the current number of the fish in the lake? Use formula T(n)=a(1+r)^n to solve problem?\r
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document.write( "-please someone help. \n" );
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Algebra.Com's Answer #373356 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! T(n)=a(1+r)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "T(n)=24000(1+(-0.06))^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "T(n)=24000(1-0.06)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "T(n)=24000(0.94)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the formula is T(n)=24000(0.94)^n \r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Now plug in T(n) = 24000/4 = 6000 and solve for n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "-------------------------------\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "T(n)=24000(0.94)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "6000=24000(0.94)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "6000/24000=(0.94)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "1/4=(0.94)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "ln(1/4) = ln((0.94)^n)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "ln(1/4) = n*ln(0.94)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "ln(1/4)/ln(0.94) = n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "n = ln(1/4)/ln(0.94)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "n = 22.4046\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So in roughly 22.4046 years, the population will be 1/4 of the current population.\r \n" ); document.write( "\n" ); document.write( "-------------------------------------------------------------------------------------------------------------- \n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Jim \n" ); document.write( "-------------------------------------------------------------------------------------------------------------- \n" ); document.write( " \n" ); document.write( " |