You can
put this solution on YOUR website!5% compounded monthly = .05/12 = .00417
present value = 2500
future value = 3500
formula is

you can solve this with logarithms.
you get

by the laws of logarithms, this becomes:

finding the logs on your calculator make the equation equal to:
3.397940009 + .001807243*x = 3.544068044
solving for x, you get:
x = 80.85690519 months
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to prove this is true, substitute in the original equation of

to get 3500.
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your answer is:

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