document.write( "Question 846572: I want to accumulate $120,000 in 30 years. Plan A is a single deposit into an account that compounds annually and an apr of 5% plan B is a single deposit into an account with continuous compounding and an apr of 4.8%
\n" ); document.write( "How much do I need to deposit into each account in order to reach my goal
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Algebra.Com's Answer #509848 by Theo(13342)\"\" \"About 
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you want $120,000 in 30 years.
\n" ); document.write( "plan A compounds annually at an apr of 5%.
\n" ); document.write( "plan B compounds continuously at an apr of 4.8%\r
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\n" ); document.write( "\n" ); document.write( "the formula for annual compounding is:
\n" ); document.write( "f = p * (1+r)^n\r
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\n" ); document.write( "\n" ); document.write( "f is the future value which is equal to 120,000
\n" ); document.write( "p is the present value.
\n" ); document.write( "r is the interest rate per time period.
\n" ); document.write( "n is the number of time periods.\r
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\n" ); document.write( "\n" ); document.write( "since the compounding is annually, than the interest rate is the apr divided by 100 which is equal to .05.
\n" ); document.write( "since the time periods are annual, then the number of time periods is the same as the number of years which is equal to 30.\r
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\n" ); document.write( "\n" ); document.write( "the formula becomes:\r
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\n" ); document.write( "\n" ); document.write( "120,000 = p * (1.05)^30.
\n" ); document.write( "divide both sides of this formula by (1.05)^30 to get:
\n" ); document.write( "120,000 / (1.05)^30 = p which makes p equal to $27,765.29.\r
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\n" ); document.write( "\n" ); document.write( "that's what you'd have to invest today at 5% compounded annually in order to have $120,000 thirty years from now.\r
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\n" ); document.write( "\n" ); document.write( "the formula for continuous compounding is:
\n" ); document.write( "f = p * e^(r*n)\r
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\n" ); document.write( "\n" ); document.write( "r is the interest rate per time period which is in years.
\n" ); document.write( "n is the number of time periods which is in years.\r
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\n" ); document.write( "\n" ); document.write( "the formula becomes:\r
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\n" ); document.write( "\n" ); document.write( "120,000 = p * e^(.048 * 30).
\n" ); document.write( "divide both sides of this equation by 3^(.048 * 30) to get:
\n" ); document.write( "120,000 / (e^(.048*30)) = p which makes p equal to 28,431.33.\r
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\n" ); document.write( "\n" ); document.write( "that's what you'd have to invest today at 5% compounded continuously in order to have $120,000 thirty years from now.\r
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