Calculating the Present Value of an Annuity with Annual Compounding

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To calculate the present value of an annuity with annual compounding, the formula used is A = P[(1 + r)^m - 1]/r, where P is the annual deposit, r is the interest rate, and m is the total number of deposits. In this case, P is $1000, r is 0.045, and m is 18. A common mistake noted is a potential typo in the formula, which should be correctly formatted as A = 1000[(1 + 0.045)^{18} - 1]/0.045. Additionally, it's pointed out that the problem may actually be a simple compound interest calculation rather than an annuity problem. Properly applying the correct formula is essential for accurate results.
TonyC
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I am having trouble with the following problem:
What will be the value of an annuity in today's dollars if $1000 is to be deposited for 18 years into an account paying 4.5% interest compounded annually?

I used the following formula (I'm guessing I've figured something incorrectly)

A= P[(1 + r)^m - 1]/r

P=1000
r=i/n
i=4.5% or .045
n=1
t=18
m=n(t) or 18

1000[1 + .045)^18 - 1/.045

I know this is incorrect because my choices are multiple choice
 
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There are a couple of possibilities. One, your last equation either has a typo or you did it wrong:

1000[1 + .045)^18 - 1/.045 ==> should be \frac{1000[(1 + .045)^{18} - 1]}{.045}

The second is that it's not an annuity problem but rather a simple compound interest problem FV = PV(1+r)^m
 
Thank you very much.
 
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