Question 1183126
.



            Do it as simple as it  SHOULD  be done.



<pre>
Your starting equation is

    {{{200(1.22)^t}}} = 13960  



Next, divide both sides by 200

    {{{(1.22)^t}}} = {{{13960/200}}}  



Next, simplify

    {{{(1.22)^t}}} = 69.8   


Next, take logarithm base 10 of both sides 


    {{{log((1.22)^t)}}} = {{{log((69.8))}}}


    {{{t*log((1.22))}}} = 1.84386


    t = {{{1.84386/log((1.22))}}}


    t=21.351     (approximately;  rounded)      <U>ANSWER</U>
</pre>

Solved.



It is a standard mantra and a standard algorithm on solving exponential equations of this type.