Need an formula/equation for this scenario

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AI Thread Summary
The discussion focuses on calculating the future value of an investment with annual contributions and compound interest. The user initially applies the compound interest formula incorrectly but later clarifies the correct formula for an annuity: N = (P/r)((1 + r)^n - 1). This formula accounts for regular annual deposits and compound interest over time. The user confirms they have resolved their confusion regarding the calculations. The conversation highlights the importance of understanding the correct application of financial formulas for accurate investment projections.
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Homework Statement


I invest 600 every year for 8% compound interest
for etc. first yr 600* 1.08= 648

2nd yr
600+648= 1248
1248*1.08= 1347.84

3rd yr
1347.84+600=1947.84
1947*1.08=2102.74

and so on

Homework Equations



compounded interest formula is

P is the principal (the money you start with, your first deposit)

r is the annual rate of interest as a decimal (5% means r = 0.05)

n is the number of years you leave it on deposit

A is how much money you've accumulated after n years, including interest.

If the interest is compounded once a year:

A = P(1 + r)power of n

The Attempt at a Solution



i attempted A= nP(1+r)power of n

but there's some difference in the answers I am getting

please help correct my formula
 
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nvm i got it

P = sum deposited at the end of each year (beginning one year from when the annuity "starts")

r = the interest rate, as a decimal (5%, for example, is r = 0.05)

n = number of years the annuity has run

N = total amount accumulated at the end of n years.

N = (P/r)( (1 + r)n - 1)
 
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