SOLUTION: How long will it take for an investment to double in value if it is invested at 5% per annum compounded monthly?

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Question 150015: How long will it take for an investment to double in value if it is invested at 5% per annum compounded monthly?
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
let t=time in months __ a=2p (doubling) __ r=.05

a=p(1+(r/12))^t __ dividing by p __ 2=(1+(.05/12)^t __ taking log __ log(2)=t*log(1+(.05/12)

dividing by log(1+(.05/12) __ [log(2)]/[log(1+(.05/12)]=t

t=166.7 (approx) __ should be 167 to get final compounding