Use the compound interest formula

A=p(1+r/n)nt
to compute the total
amount of the investment if $7500 is invested at 9% compounded monthly for
4 years.

2 answers

The "nt" in your equation is an exponent and should be written ^nt, since we can only write numbers on a single line here. n is the number of interest-componding periods in a year (12), at t is the number of years (4).

In your case, r/n = 9%/12 = .0075, and nt = 48

Therefore A = 7500(1.0075)^48
= 7500*1.4314053
= 10,733.54
I used a hand calculator to take the 48th power of 1.0075.
Thanks a lot