document.write( "Question 1157134: this exercise uses the population growth model.\r
\n" ); document.write( "\n" ); document.write( "A certain species of bird was introduced in a certain county 25 years ago. Biologists observe that the population doubles every 10 years, and now the population is 19,000.
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\n" ); document.write( "\n" ); document.write( "(b) Estimate the bird population 7 years from now. (Round your answer to the nearest whole number.)
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Algebra.Com's Answer #779950 by ikleyn(52782) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "(a)  Original population was  19000/(2^(25/10)) =  = 3359 (rounded).   ANSWER\r\n" );
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document.write( "         2.5 here is the number of doubling periods in 25 years.\r\n" );
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document.write( "(b)  Population in 7 years from now will be  19000*2^(7/10) =  = 30866  (rounded).    ANSWER\r\n" );
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document.write( "          = 0.7  here is the number of doubling periods in 7 years.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Added after seening the post by @Boreal.\r
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document.write( "    In this problem, all the data are presented in terms of a doubling period.\r\n" );
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document.write( "    It assumes, that the entire solution should be made in these terms.\r\n" );
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document.write( "    It really can be done in terms of doubling period, and a good style ASSUMES that it will be done in these terms.\r\n" );
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document.write( "    Transition to another forms of an exponential model is possible, in principle, but it means \r\n" );
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document.write( "    performing UNNECESSARY calculations, where you can make errors and may lose a precision in your calculations.\r\n" );
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document.write( "        Therefore, I strongly recommend to solve such problems in terms of doubling periods.\r\n" );
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document.write( "    Again: when the input data are in terms of doubling period, it is logically right way to make all calculations in this frame.\r\n" );
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document.write( "    Doing another way, you perform TONS of unnecessary calculations and create unnecessary problems for yourself\r\n" );
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document.write( "    and do everything to lower your reputation.\r\n" );
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