find the compound interest due in 6 years if 11,300 is invested at 9% compounded quarterly

Question

compound amount and compound interest formula

Answer 1

9% annually is 9/4=2.25% quarterly. After one quarter the amount grows by 1.0225. After 2 quarters it's 1.0225^2, and so on. After 24 quarters (6 years), the growth is 1.0225^24=1.7058 approx. This is applied to the principal 11,300 so after 6 years the amount is 19,275.16, so the interest is 7,975.16.