Compound interest formula:
A = P (1 + r/n )^nt
Where:
A = future vale
P= Principal investment = 9,000
r = interest rate in decimal form = 9/100 = 0.09
n = number of compounding periods = 4
t = years = 8
Replacing:
A = 9000 ( 1 + 0.09/4)^ (4*8)
A = 9000 (1.0225)^32
A= 18,342.93
The future value is $18,342.93