<PRE><B>Question 1135128</B>
the formula for simple interest is i = p * r * t.


i is the interest.
p is the principal.
r is the interest rate per time period.
n is the number of time periods.


in your problem:


i = 6568.80
n = 5
r = 8.4% / 100 = .084


the time period is years.


plug those values into the formula to get 6568.80 = p * .084 * 5


solve for p to get p = 6568.80 / (.084 * 5) = 15640.


she borrowed 15,640 dollars at 8.4% simple interest.


test your formula with this value to confirm the solution is good.


15640 * .084 * 5 = 6568.8, confirming the solution is good.



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