Question 1203684
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The hourly wage of some automobile plan workers went from 7.90 to 13.35 in 9 years annual raises 
if their wages are growing exponentially what will be their hourly wage in 3 more years. Nearest (0.10)
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<pre>
In this problem, we have given the exponential raise for 9 years,
and the question asks about this exponential function 3 years later.


In order for to make calculations minimal, I will apply a trick: I will find first 
the coefficient of growth in 3 years, and then will use it to answer the question.


So, let R be the coefficient of growth in 3 year. Then I can write this equation

    13.35 = {{{7.90*R^3}}},

or

    {{{13.35/7.90}}} = {{{R^3}}},

    1.689873418 = {{{R^3}}}

    R = {{{root(3,1.689873418)}}} = 1.191108685.


Having it, the answer to the problem's question is in one line:

    their hourly wage in 3 more year is  13.35*1.191108685 = 15.90  (rounded as requested).    <U>ANSWER</U>
</pre>

Solved.