Question 1150563
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Let x be the Jon's age.


Then from the problem's description, you have this equation


    {{{(x-5)/5}}} = 15.


Solve it.  Your first step is to multiply both sides by 5.


    x - 5 = 5*15 = 75

     x           = 75 + 5 = 80.    <U>ANSWER</U>


<U>ANSWER</U>.  Jon is 80 years old.
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