The Math department purchased a copy machine for $ 12000. After3years, the machine will be worthless. How much money should the department deposit at the end of each quarter, if the money is worth8%compounded quarterly, in order to save enough to buy a new copy machine at the end of 3years?

If I understand correctly, this is a compound interest question (A=P*(1+r/n)^(nt)), where:

P = 12000

r = 0.08

t = 3

A = ?

n = 4

but not sure, if that is correct and how to continue from here. Thank you!