document.write( "Question 79656: Please help me with this problem.I am having a lot of issues with these types of problems.I tried plugging in 200 for P and 3 for t but I still cant get it right.\r
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document.write( "The population P of a certain culture is expected to be given by a model P=100e^rt where r is a constant to be determined and t is the number of days since the original population is expected to reach 200 in 3 days.
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document.write( "a. 0.231
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document.write( "b. 0.549
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document.write( "c. 1.098
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document.write( "d. 1.50 \n" );
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Algebra.Com's Answer #57163 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! The population P of a certain culture is expected to be given by a model P=100e^rt where r is a constant to be determined and t is the number of days since the original population is expected to reach 200 in 3 days. \n" ); document.write( ": \n" ); document.write( "100(e^rt) = P \n" ); document.write( ": \n" ); document.write( "Substitute for t and P \n" ); document.write( "100(e^(3r)) = 200 \n" ); document.write( ": \n" ); document.write( "Divide both sides by 100 and you have: \n" ); document.write( "e^(3r) = 2 \n" ); document.write( ": \n" ); document.write( "Find nat log of both sides: \n" ); document.write( "ln(e^3r) = ln(2) \n" ); document.write( ": \n" ); document.write( "3r*ln(e) = ln(2); log equiv of exponents \n" ); document.write( ": \n" ); document.write( "3r = .693147; remember ln(e) = 1 \n" ); document.write( ": \n" ); document.write( "r = .693147/3 \n" ); document.write( ": \n" ); document.write( "r = .231 \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check solution with a good calc: enter 100(e^(.231*3)) = 199.97 ~ 200 \n" ); document.write( " |