Question 1139100
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<pre>

Let "n" be the number of quarter periods.


24000 = {{{20000*(1+0.0514/4)^n}}},


{{{24000/20000}}} = {{{(1+0.0514/4)^n}}}


1.2 = {{{(1+0.0514/4)^n}}}


log(1.2) = {{{n*log((1+0.0514/4))}}}


n = {{{log((1.2))/log((1+0.0514/4))}}} = 14.28 quarter periods.



<U>ANSWER</U>. 15 quarter periods are enough.


<U>CHECK</U>.  {{{20000*(1+0.0514/4)^15}}} = 24221.83 dollars.
</pre>

Solved.