Question 1130374
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<pre>
The formula for the future value of a principle compounded continuously, under given conditions is


    FV = {{{P*e^(0.058*t)}}},


where P is the principle investment amount and  t  is the time in years.


So, the problem asks, when it will happen that


    2P = {{{P*e^(0.058*t)}}}.


It impliues


    2 = {{{e^(0.058*t)}}}


    ln(2) = t*0.058


    t = {{{ln(2)/0.058}}} = 11.95 years,   or about 12 years.


<U>Answer</U>.  11.95 years;  12 years is enough.
</pre>

Solved.


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The solution by @addingup is incorrect.