Posted by twayne on Thursday, July 19, 2012 at 4:27pm.
How long will it take for an investment of $13,000 to double if the investment earns interest at the rate of 6%/year compounded continuously?

math  Reiny, Thursday, July 19, 2012 at 6:27pm
13000 e^.06t = 26000
e^.06t = 2
take ln of both sides
ln e^.06t = ln 2
.06t ln e = ln2 , but lne = 1
t = ln2/.06
= appr 11.55