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You are not logged in. #1 20130823 16:49:43
Compound interest on investmentI am new to the forum, so hello to everybody. Please help, I would like to know the formula for the following situation: The investor takes out an investment of $450 per month every month for 5 years, interest rate is 10% per annum, how do I calculate the total value after 5 years? This can be calculated easily on a financial calculator, but I would like to know the formula. Thank you. #2 20130824 03:32:47
Re: Compound interest on investmenthi CJVR Now work through a few months to establish a pattern. Start of month one End of month one Start of month two End of month two Start of month three End of month three So after 60 months Using the formula for the sum of a GP In the screen shot below I have worked through 3 months like this and then used the formula to check the formula gives the same value. http://www.mathsisfun.com/algebra/seque … etric.html As I've just made this up it would be great to know that a financial calculator gives the same results. NEXT DAY EDIT: I tried http://www.thisismoney.co.uk/money/savi … lator.html It made it £34846.68 whereas my formula made it £34727.28 (using Excel) This calculator only accepts interest rates to 2 dp so it is not clear whether my formula is wrong or whether their's is insufficiently accurate. I'll try to find a more accurate one. A LITTLE LATER: http://www.calculatorweb.com/calculator … calc.shtml gives 35877.46 Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #3 20130824 19:27:33
Re: Compound interest on investmentFinal offering for now: You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei 