(a) 6% of the value of the investment is added each year. This means the value of the investment is multiplied by 1.06 each year. After 15 multiplications, the value is ...
... $3000×1.06¹⁵ ≈ $7189.67
(b) The interpretation of this result is ...
... After 15 years, the investment is worth $7189.67.