Question 1196114
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You currently have $8,800 (Present Value) in an account that has an interest rate 
of 6% per year compounded daily (365 times per year). You want to withdraw all your 
money when it reaches $16,720 (Future Value). In how many years will you be able 
to withdraw all your money?
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<pre>
Let "r" be the compound interest rate per annum.

Start from the formula for the future value

    16720 = {{{8800*(1+0.06/365)^n}}},

where "n" is the number of days.


It is the same as

    {{{16720/8800}}} = {{{1.000164384^n}}},

or

    1.9 = {{{1.000164384^n}}}.



Take logarithm base 10 of both sides of the equation

    log(1.9) = n*log(1.000164384).


Find  n = {{{log((1.9))/log((1.000164384))}}} = 3904.92 days, or 3905 days, rounded to the closest greater number of days.


3905 days = 10 years 8 months and about 12 days  (counting 365 days/year, 30 days per month).


<U>ANSWER</U>. The time to wait is 3905 days, or 10 years, 8 months and about 12 days.
</pre>

Solved.