How much would $300 invested at 9% interest compounded monthly be worth after 3 years?

F=P(1+(r/n))^(nt)

F=future amount

P=present amount

r=rate in decimal form

n=number of times per year it is compounded

t=time in years

F=P(1+(r/n))^(nt)

F=future amount

P=300

r=0.09

n=1

t=3

F=300(1+(0.09/1))^(1(3))

F=300(1+0.09)^(3)

F=300(1.09)^(3)

F=388.509

it would be worth $388.51 (rounded)