Hey guys just wondering if you could help me figure this one out?

An asset purchased at the beginning of the financial year is expected to return $5000 at the end of the current financial year,$10000 at the end of the next financial year and $15000 at the end of the following financial year. Determine the present value of these expected returns, assuming capital can be invested at 6% per annum, payable quarterly. I already have the answer of$26133.84
I need assistance with the working out to get the answer?
The Present value formula is P= R(1-(1+i)^-n)/i

2. Why do you need a formula for a series of equal payments to compute the present value of three unequal cash flows? You seem to be missing something on this assignment.

APR = 0.06
Compounded Quarterly: 0.06/4 = 0.015
Quarterly Discount: 1/1.015 = 0.985221675 = QD
Annual Discount: $\displaystyle QD^{4} = 0.942184230 = v$
Calculate: $\displaystyle 5000v + 10000v^{2} + 15000v^{3}$

Alternatively, and maybe a little cleaner.
APR = 0.06
Compounded Quarterly: 0.06/4 = 0.015
Quarterly Discount: 1/1.015 = QD = v^{(4)}
Calculate: $\displaystyle 5000[v^{(4)}]^{4} + 10000[v^{(4)}]^{8} + 15000[v^{(4)}]^{12}$

Even if you get this, you may wish to review a section or two and make sure you know where you are headed.