document.write( "Question 16752: How many years will it take $5,000 to grow to $7,500 if it is invested at 8% compounded semiannually?\r
\n" ); document.write( "\n" ); document.write( "Compounded continously?
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Algebra.Com's Answer #8171 by bam878s(77)\"\" \"About 
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we are given annual interest rate i = 8% or .08
\n" ); document.write( "the semiannual interest rate is then \"i%2F2\" = \".08%2F2\" = .04
\n" ); document.write( "the per period accumulation function is then \"%281+%2B+.04%29%5En\"
\n" ); document.write( "so, we have 7500 = 5000 * \"%281+%2B+.04%29%5En\". First divide 5000 from both sides.
\n" ); document.write( "1.5 = \"%281+%2B+.04%29%5En\"
\n" ); document.write( "log 1.5 = n log 1.04
\n" ); document.write( "divide log 1.04 from both sides
\n" ); document.write( "n = 10.3380351 half years or 5.1690175 years.\r
\n" ); document.write( "\n" ); document.write( "For continous interest we need to find the force of interest (d) over the accumulation period.
\n" ); document.write( "we know \"%281+%2B+i%29%5En\" = \"e%5E%28nd%29\"
\n" ); document.write( "so \"%281+%2B+.08%29%5En\" = \"e%5E%28nd%29\"
\n" ); document.write( "n ln 1.08 = nd (take the natural log of both sides)
\n" ); document.write( "ln 1.08 = d
\n" ); document.write( "now the accumulation function for continuous interest is \"e%5E%28nd%29\"
\n" ); document.write( "so 5000 * \"e%5E%28n+%2A+ln+1.08%29\" = 7500
\n" ); document.write( "\"e%5E%28n+%2A+ln+1.08%29\" = 1.5
\n" ); document.write( "\"n+%2A+ln+1.08\" = ln 1.5 (take the natural log of both sides)
\n" ); document.write( "n = \"ln+1.5%2F+ln+1.08\"
\n" ); document.write( "n = 5.2684462\r
\n" ); document.write( "\n" ); document.write( "Hope this helps, let me know if you have any more financial mathematics questions. I know them fairly well.
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