Question 1206514
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If you make quarterly deposits of $407 into an ordinary annuity earning an annual interest rate of 6.52%, 
how much will be in the account after 8 years? How much interest did you earn in 8 years?
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Use a standard formula for the future value of an ordinary annuity

    FV = {{{D*(((1+r)^n-1)/r)}}}.


Here  'D'  is the quarterly deposit of  $407;  'r'  is the effective interest rate 
per quarter r = 0.062/4;  'n'  is the number of deposits n = 4*8 = 32 (same as the number of quarters.


Thus you have

    FV = {{{407*(((1+0.0652/4)^32-1)/((0.0652/4)))}}} = 16,920.49.


This is the value at the account in 8 years.


You deposited  8*4*407 = 13024 dollars.


The interest is the difference 16,920.49 - 13024 = 3896.49 dollars.
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