document.write( "Question 1026385: This exercise uses the population growth model. \r
\n" ); document.write( "\n" ); document.write( "A culture starts with 8700 bacteria. After 1 hour the count is 10,000.
\n" ); document.write( "(a) Find a function that models the number of bacteria n(t) after t hours. (Round your r value to three decimal places.)
\n" ); document.write( "n(t) =
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\n" ); document.write( "\n" ); document.write( "(b) Find the number of bacteria after 2 hours. (Round your answer to the nearest hundred.)
\n" ); document.write( "_____bacteria \r
\n" ); document.write( "\n" ); document.write( "(c) After how many hours will the number of bacteria double? (Round your answer to one decimal place.)
\n" ); document.write( "_____hr
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Algebra.Com's Answer #641630 by josgarithmetic(39620)\"\" \"About 
You can put this solution on YOUR website!
p for population
\n" ); document.write( "x for time in hours
\n" ); document.write( "\"p=8700%2Ae%5E%28kx%29\"\r
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\n" ); document.write( "\n" ); document.write( "Solve the model for k.
\n" ); document.write( "\"ln%28p%29=ln%288700%29%2Bkx%2Aln%28e%29\"
\n" ); document.write( "\"kx%2A1=ln%28p%29-ln%288700%29\"
\n" ); document.write( "\"k=%281%2Fx%29%28ln%28p%29-ln%288700%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Substitute the point (1,10000).
\n" ); document.write( "\"k=%281%2F1%29%28ln%2810000%29-ln%288700%29%29\"
\n" ); document.write( "\"k=ln%2810000%29-ln%288700%29\"
\n" ); document.write( "\"k=0.13926\"-----which you might want only to three significant figures, or maybe just two.\r
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\n" ); document.write( "\n" ); document.write( "If you want p after 2 hours, you could simply use \"10000%2810000%2F8700%29\" and it SHOULD be the same as \"8700%2Ae%5E%280.139%2A2%29\"; just try it /them and see. The model more specifically is \"highlight%28p=8700%2Ae%5E%280.139%2Ax%29%29\".\r
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\n" ); document.write( "\n" ); document.write( "Find x for how long to double.
\n" ); document.write( "Take logs of both sides and solve for x.
\n" ); document.write( "More simply, \"2=1%2Ae%5E%280.13926%2Ax%29\"---------start from this form.
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