Need some help solving this Please provide a detailed exampl

Need some help solving this. Please provide a detailed example.

Find the interest rate needed for the sinking fund to reach the required amount. Assume that the compounding period is the same as the payment period. $18,010 to be accumulated in 3 years; quarterly payments of $1375.

Solution

Payment quarterly =$ 1375 =P

no of times = N(N+1)/2 = 12 x13 /2 = 78 =

Amount = 18010

A= P T R / 3 where R is the interest rate per year ( quarterly =.3 months )

18010 = 1375 x 78 xR /3 => R = 6 % per annum