Question 508544
How long will it take to double my investment (which they don't tell me) with compound annual investment
FV = PV*(1 + r)^n  r = interest rate per period, n = # of periods
FV = 2*PV
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(1 + r)^n = 2
n*log(1 + r) = log(2)
n = log(2)/log(1 + r)
The value of n depends on the interest rate.
The amounts are not relevant, whatever you start with is doubled.
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compound monthly:
Same as above, but the monthly interest rate = annual rate/12, and n is the # of months.
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and compound continuously.
FV = PV*e^rt, r = rate per period, t = periods
e^rt = 2
rt = ln(2)
t = ln(2)/r
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You have to use ln (natural logs) for this one.  The 1st 2 can be log or ln.
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please explain in detail
FV = Future Value
PV = Present Value
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