document.write( "Question 266547: The population of a particular city is increasing at a rate proportional to its size. It follows the function P(t) = 1 + ke0.12t where k is a constant and t is the time in years. If the current population is 15,000, in how many years is the population expected to be 37,500? Round to the nearest year
\n" ); document.write( "51
\n" ); document.write( "8
\n" ); document.write( "5
\n" ); document.write( "3
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Algebra.Com's Answer #195831 by drk(1908)\"\" \"About 
You can put this solution on YOUR website!
By saying current population, we create the coordinate: (0, 15000). We put that into
\n" ); document.write( "(i) \"P%28t%29+=+1+%2B+ke%5E%280.12t%29\"
\n" ); document.write( "to get
\n" ); document.write( "(ii) \"15000+=+1+%2B+ke%5E%280.12%2A0%29\"
\n" ); document.write( "which is simply
\n" ); document.write( "(iii) \"1500+=+1+%2B+k\"
\n" ); document.write( "so k = 14999
\n" ); document.write( "Now, we rewrite the equation with our new k to get
\n" ); document.write( "(iv) \"P%28t%29+=+1+%2B+14999e%5E%280.12%2At%29\"
\n" ); document.write( "We are given 37000 as our new population number, place that into the equation and solve for t. we get
\n" ); document.write( "(v) \"37000+=+1+%2B+14999e%5E%280.12%2At%29\"
\n" ); document.write( "subtract 1 and then divide by 14999 to get
\n" ); document.write( "(vi) \"2.46676+=+e%5E%280.12%2At%29\"
\n" ); document.write( "take an \"LN\" of both sides to get
\n" ); document.write( "(vii) \".902907+=+%280.12%2At%29\"
\n" ); document.write( "divide to get
\n" ); document.write( "(viii) \"t+=+7.524\" years
\n" ); document.write( "-----
\n" ); document.write( "to the nearest year, it is 8.
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