<PRE><B>Question 1056826</B>
The simple interest formula will suffice
   
    {{{ F = P ( 1 + rt ) }}}

where
      F = future value of investment
      P = present value of investment
      r = interest rate
      t = number of periods

 In this problem  F=25000,  t=8yrs, and P=15000.   The problem asks us to find the rate r.

          25000 = 15000(1 + r*8)
          25000/15000 = (1 + r*8)
          25/15 - 1 = r*8
          10/15       = r*8
          10/(15 * 8) = r
               r = 0.08333…      ( 8.33333... % )
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