document.write( "Question 1198391: Find the time needed to Reach an investment goal if you want to say 5000 before buying your first new car and you have 3000 right now tp invest at 3% interest compound monthley
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Algebra.Com's Answer #831977 by Theo(13342)\"\" \"About 
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you can use a financial calculator or you can use the following formula.
\n" ); document.write( "f = p * (1 + r) ^ n
\n" ); document.write( "f is the future value
\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( "in your problem:
\n" ); document.write( "f = 5000
\n" ); document.write( "p = 3000
\n" ); document.write( "r = .03/12
\n" ); document.write( "n = number of months.\r
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\n" ); document.write( "\n" ); document.write( "formula becomes:
\n" ); document.write( "5000 = 3000 * (1 + .03/12) ^ n
\n" ); document.write( "divide both sides of the equation by 3000 to get 5/3 = (1 + .03/12) ^ n
\n" ); document.write( "simplify to get 5/3 = 1.0025 ^ n
\n" ); document.write( "take the log of both sides of the equation to get:
\n" ); document.write( "log(5/3) = log(1.0025^n) which becomes:
\n" ); document.write( "log(5/3) = n * log(1.0025)
\n" ); document.write( "divide both sides of the equation by log(1.0025) to get:
\n" ); document.write( "log(5/3) / log(1.0025) = n
\n" ); document.write( "solve for n to get:
\n" ); document.write( "n = 204.585556.
\n" ); document.write( "confirm by replacing n with that and solving for f in the original equation to get:
\n" ); document.write( "f = 3000 * (1 + .03/12) ^ 204.585556 = 5000\r
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\n" ); document.write( "\n" ); document.write( "the 3000 will grow to 5000 in 204.585556 months = 17.04879634 years.\r
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\n" ); document.write( "\n" ); document.write( "if you used a calculator such as the one at https://arachnoid.com/finance/, you would get n = 204.59.
\n" ); document.write( "that's the same answer as from the formula, except rounded to 2 decimal places.\r
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\n" ); document.write( "\n" ); document.write( "here are the results from using that calculator.\r
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\n" ); document.write( "\n" ); document.write( "since the interest rate is compounded monthly, then you need to get the monthly interest rate and you are solving for the number of months.
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