document.write( "Question 722987: how long will it take for the populations of a certain country to double if its annual growth rate is 6.2%? \n" ); document.write( "

Algebra.Com's Answer #442975 by josmiceli(19441) $\"\"$ $\"About$

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Let P[n] = population after $\"+n+\"$ years
\n" ); document.write( "Let $\"+P+\"$ = the starting population
\n" ); document.write( " $\"+r+\"$ = rate of growth of population
\n" ); document.write( "------------
\n" ); document.write( " $\"+P%5Bn%5D+=+P%2A%28+1+%2B+r+%29%5En+\"$
\n" ); document.write( "given:
\n" ); document.write( " $\"+2P+=+P%2A%28+1+%2B+.062+%29%5En+\"$
\n" ); document.write( " $\"+2+=++1.062%5En+\"$
\n" ); document.write( " $\"+log%282%29+=+n%2Alog%281.062%29+\"$
\n" ); document.write( " $\"+n+=+log%282%29+%2F+log%281.062%29+\"$
\n" ); document.write( " $\"+n+=+.30103+%2F+.02612+\"$
\n" ); document.write( " $\"+n+=+11.525+\"$ yrs
\n" ); document.write( " $\"+.525%2A12+=+6.3+\"$
\n" ); document.write( " $\"+.3%2A30+=+9+\"$
\n" ); document.write( "It will take 11 years 6 months and 9 days
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\n" ); document.write( " \n" ); document.write( "

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