SOLUTION: What annual rate of interest compounded yearly is required to double an investment in 4 years?

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Question 691324: What annual rate of interest compounded yearly is required to double an investment in 4 years?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What annual rate of interest compounded yearly is required to double an investment in 4 years?
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A(t) = P(1+(r/n))^(nt)
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Your problem requires that (1+(r/n))^(nt) = 2
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(1 + (r/1))^(1*4) = 2
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(1+r)^4 = 2
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4*log(1+r) = log(2)
log(1+r) = (1/4)*0.3010
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log(1+r) = 0.0753
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1+r = 10^0.0753
1+r = 1.1892..
rate = 0.1892.. = 18.92%
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Cheers,
Stan H.
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