Question 1111067
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<pre>
Let "x" be the interest rate under the question (as percentage).


Then, since it is <U>SIMPLE INTEREST</U> (according to the condition)


12000 = {{{6000*(1 + (x/100)*14)}}},


which implies  2 = {{{12000/6000}}} = {{{1 + (x/100)*14}}}, 


x = {{{100/14}}} = 7.1%   (rounded to the nearest tenth of a percent).
</pre>

Solved.



<U>Be aware</U>:  &nbsp;&nbsp;The solution by &nbsp;@Boreal is &nbsp;&nbsp;<U>W R O N G</U> &nbsp;&nbsp;and &nbsp;&nbsp;<U>I R R E L E V A N T</U>.