<PRE><B>Question 603915</B>
Given A=P(1+r/n)^nt find how long it takes for an investment to double if it is invested at 5% interest compounded quarterly.
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Solve:  2P = P(1+ (.05/4))^(4t)
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(1.0125)^(4t) = 2
(4t) = ln(2)/ln(1.0125) 
4t = 55.7976
t = 13.95 years
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Cheers,
Stan H.
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