You have 10,000 invested at 8% interest per annum. How much interest is earned in 2 years, 4 months?
after 2 years you will have 10000(1.08)^2 = 11664.00
so you have earned $664.00 in interest
It says the interest is 8% per annum, so we must assume it is
compounded annually unless otherwise stated.
since the interest is compounded annually, that is, it is added only
at the end of each year, after 4 months you still only have earned $664.00