document.write( "Question 960412: how many years would it take at 10% per year for $1360 to double? \n" ); document.write( "

Algebra.Com's Answer #586946 by josmiceli(19441) $\"\"$ $\"About$

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$\"+2%2A1360+=+2720+\"$
\n" ); document.write( "Let $\"+n+\"$ = the number of years it
\n" ); document.write( "takes for $1360 to double
\n" ); document.write( "-------------------------
\n" ); document.write( " $\"+2720+=+1360%2A%28+1+%2B+.1+%29%5En+\"$
\n" ); document.write( " $\"+2720+=+1360%2A%281.1%29%5En+\"$
\n" ); document.write( "Take the log of both sides
\n" ); document.write( " $\"+log%28+2720+%29+=+log%28+1360+%29+%2B+log%28+%281.1%29%5En+%29+\"$
\n" ); document.write( " $\"+log%28+2720+%29+=+log%28+1360+%29+%2B+n%2Alog%28%28+1.1+%29%29+\"$
\n" ); document.write( " $\"+3.4346+=+3.1335+%2B+n%2A.04139+\"$
\n" ); document.write( " $\"+n%2A.04139+=+.3011\"$
\n" ); document.write( " $\"+n+=+.3011+%2F+.04139+\"$
\n" ); document.write( " $\"+n+=+7.2747+\"$
\n" ); document.write( "It would take about 7 years and 4 months
\n" ); document.write( "check:
\n" ); document.write( " $\"+2720+=+1360%2A%28+1+%2B+.1+%29%5En+\"$
\n" ); document.write( " $\"+2720+=+1360%2A%28+1+%2B+.1+%29%5E7.2747+\"$
\n" ); document.write( " $\"+2720+=+1360%2A2.0004+\"$
\n" ); document.write( " $\"+2720+=+2720.544+\"$
\n" ); document.write( "error due to rounding off
\n" ); document.write( "close enough to get the year and month\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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