Question 1119019
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The given numbers for the initial investment and the amount after 10 years are irrelevant.  The interest rate is exactly determined knowing that the doubling time is 11 years.<br>
{{{e^(11r) = 2}}}
{{{11r = ln(2)}}}
{{{r = ln(2)/11 = 0.063}}} to 3 decimal places.<br>
The given initial amount and the amount after 10 years are consistent with that interest rate; but neither of those numbers is needed to determine the interest rate, which is what the question asked for.