document.write( "Question 256355: i'm doing business algebra online in college, and we're now talking about continuous compound interest. The formula i'm struggling with is the Pert formula. I'm stuck on how to solve a problem when i know what the P, r and t is, but what is the e for? I've never figured out how to come up with the same answer as my study guide example.\r
\n" ); document.write( "\n" ); document.write( "For example: Use the continuous compound interest formula to find the indicated value. A=$7,700; r=8.78%; t=10 years; P=? P=_______(round to two decimal places as needed).\r
\n" ); document.write( "\n" ); document.write( "I look forward to getting a reply back soon. Hopefully I will get this figured out soon. Thank you.
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Algebra.Com's Answer #188489 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
with continuous compounding formula, you get:\r
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\n" ); document.write( "\n" ); document.write( "\"f+=+p+%2A+e%5Ert\"\r
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\n" ); document.write( "\n" ); document.write( "f = future value
\n" ); document.write( "p = present amount
\n" ); document.write( "r = annual interest rate
\n" ); document.write( "t = number of years\r
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\n" ); document.write( "\n" ); document.write( "the e is the symbol for the scientific constant of 2.718281828...\r
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\n" ); document.write( "\n" ); document.write( "This is an irrational number (never ending non repeating fractional part).\r
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\n" ); document.write( "\n" ); document.write( "It's called Napier's constant.\r
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\n" ); document.write( "\n" ); document.write( "the formula for the base of e to an exponent is \"e%5Ex\" where x is the exponent.\r
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\n" ); document.write( "\n" ); document.write( "the inverse formula of \"e%5Ex\" is equal to \"ln%28x%29\" which means the natural log of x.\r
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\n" ); document.write( "\n" ); document.write( "the basis definition of \"e%5Ex\" is:\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+e%5Ex\" if and only if \"x+=+ln%28y%29\".\r
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\n" ); document.write( "\n" ); document.write( "this is nothing more than your normal logarithm functions except you have a base of e.\r
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\n" ); document.write( "\n" ); document.write( "It's no different than the statement:\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+10%5Ex\" if and only if \"log%2810%2Cx%29+=+y\"\r
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\n" ); document.write( "\n" ); document.write( "for example:\r
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\n" ); document.write( "\n" ); document.write( "let x = 3\r
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\n" ); document.write( "\n" ); document.write( "{y = 10^3}}} = 10*10*10 = 1000\r
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\n" ); document.write( "\n" ); document.write( "the statement becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+10%5E3\" if and only if \"log%2810%2C1000%29+=+3\".\r
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\n" ); document.write( "\n" ); document.write( "you can confirm that \"log%2810%2C1000%29+=+3\" by using your calculator and taking the log of 3. \r
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\n" ); document.write( "\n" ); document.write( "you will get 1000.\r
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\n" ); document.write( "\n" ); document.write( "the base e is nothing more than another base to work with.\r
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\n" ); document.write( "\n" ); document.write( "In your problem, here's how you would work it.\r
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\n" ); document.write( "\n" ); document.write( "formula is \"f+=+p+%2A+e%5Ert\".\r
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\n" ); document.write( "\n" ); document.write( "you are given:\r
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\n" ); document.write( "\n" ); document.write( "p = $7,700
\n" ); document.write( "r = 8.78%
\n" ); document.write( "t = 10 years\r
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\n" ); document.write( "\n" ); document.write( "first thing you need to do is take all the dollar signs and commas out of p to get:\r
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\n" ); document.write( "\n" ); document.write( "p = 7700\r
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\n" ); document.write( "\n" ); document.write( "next thing you need to do is divide 8.78% by 100% to get .0878.\r
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\n" ); document.write( "\n" ); document.write( "in the formula, you need to work with the rate, not the percent.\r
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\n" ); document.write( "\n" ); document.write( "since r is an innual interest rate already, you do not need to adjust it any further.\r
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\n" ); document.write( "\n" ); document.write( "since t is already specified in years, you do not need to adjust it any further.\r
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\n" ); document.write( "\n" ); document.write( "plug these values into your formula to get:\r
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\n" ); document.write( "\n" ); document.write( "\"f+=+p+%2A+e%5Ert\" becomes\r
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\n" ); document.write( "\n" ); document.write( "\"f+=+7700+%2A+e%5E%28.0878%2A10%29\"\r
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\n" ); document.write( "\n" ); document.write( "simplify to get:\r
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\n" ); document.write( "\n" ); document.write( "\"f+=+7700+%2A+e%5E%28.878%29\"\r
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\n" ); document.write( "\n" ); document.write( "use your calculator to get \"e%5E%28.878%29\" = 2.406082726\r
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\n" ); document.write( "\n" ); document.write( "alternatively, you can substitute the constant of 2.718281828 to get:\r
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\n" ); document.write( "\n" ); document.write( "solve for f to get:\r
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\n" ); document.write( "\n" ); document.write( "f = 18526.83699\r
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\n" ); document.write( "\n" ); document.write( "that's equivalent to $18,526.84.\r
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\n" ); document.write( "\n" ); document.write( "for some good examples of continuous compounding, check out the web.\r
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\n" ); document.write( "\n" ); document.write( "do a search on \"continuous compounding\".\r
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\n" ); document.write( "\n" ); document.write( "one such website is http://moneychimp.com/articles/finworks/continuous_compounding.htm\r
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\n" ); document.write( "\n" ); document.write( "It has a calculator that lets you calculate different numbers and see the effect of continuous compounding compared to discrete compounding such as yearly, monthly, daily, and hourly.\r
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\n" ); document.write( "\n" ); document.write( "It also has a box where you can put in the number of time periods you want.\r
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