Question 1137562
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30 months = 2.5 years.


{{{P*e^(r*2.5)}}} = 2*P,   where P is the principal.


2.5*r = ln(2)


r = {{{ln(2)/2.5}}} = 0.2773 = 27.73%


<U>ANSWER</U>.  0.2773,  or  27.73% annual interest rate compounded continuously.
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