Brianna deposits $150 at the end of each quarter into an account that pays 8% compounded quarterly for 9 months. calculate the amount in the account at the end of the period.

I did this ..

150[(1 + .08)^9x3 – 1]
3
divide the top half by .08/3
= 150[(1+0.027)^27-1]
divide the top half by the bottom half 0.027

= 5,850.34
that can’t be right only after 9 months.