Question 1141913
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You want the future value, V(t), to be twice the present value, V(0):<br>
{{{V(0)e^(0.087t) = 2V(0)}}}
{{{e^(0.087t) = 2}}}<br>
Since the unknown is in an exponent, you need to use logarithms.<br>
{{{ln(e^(0.087t)) = ln(2)}}}
{{{0.087t = ln(2)}}}<br>
You can finish from there.