Question 1203317
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<pre>

From the problem, we have this equation

    3.95 = {{{4.69*1.035^t}}}


We transform it in a standard way

    {{{3.95/4.69}}} = {{{1.035^t}}}

    0.842217 = {{{1.035^t}}}.


Then take logarithm base 10 of both sides

    {{{log((0.842217))}}} = {{{t*log((1.036))}}}


and find t

    t = {{{log((0.842217))/log((1.035))}}} = -4.99158


which we round to 5 years.


So, the event under the problem's question happened 5 years before the year 2020.


<U>ANSWER</U>.  The closest year is 2015, option (D).
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Solved.