document.write( "Question 1102063: A group of 30 fish of a certain species is released in lake.With a careful management the number of fish.N,t years is expected that\r
\n" ); document.write( "\n" ); document.write( "N=330/{ 1+10(0.81)^T }\r
\n" ); document.write( "\n" ); document.write( "and the fish population will be able to maintain itself without ay protection when the population reaches a size of 80.How many years must a protection program be maintained for the fish population? \n" ); document.write( "

Algebra.Com's Answer #716705 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Mathematically, the question is:  at which t the quantity\r\n" );
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document.write( "N = 330/(1+10(0.81)^t) = \r\n" );
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document.write( "will reach the value of 80.\r\n" );
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document.write( "I will show the plot first\r\n" );
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document.write( "Plot y = \r\n" );
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document.write( "Next, I will show the table\r\n" );
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document.write( "Year, t    N = 330/(1+10(0.81)^t\r\n" );
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document.write( "  0	       30.00\r\n" );
document.write( "  1	       36.26\r\n" );
document.write( "  2	       43.65\r\n" );
document.write( "  3	       52.26\r\n" );
document.write( "  4	       62.21\r\n" );
document.write( "  5	       73.55\r\n" );
document.write( "  6	       86.29\r\n" );
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document.write( "From the plot and from the table you can see that the number N increases monotonically and will exceed the value of 80 in 6 years.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Answer. How many years must a protection program be maintained for the fish population? - 6 years.\r
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