I=prt . Where: P = Principal Amount; I = Interest Amount; r = Rate of Interest per year in decimal and time t should be in the same time units such as months or years.
8% of 500 is 40, For the first year is 540. 8% of 540 is 43.20 dollars. 8% of 583.2 is 46.656. So the total is 630 by rounding but the actual amount is 629.956. The interest is 129.956
