You are given the equation
A(t) = P*e^(rt)
Where P = Principal
r = interest rate
t = time
e is a mathematical constant equivalent to approx 2.71828
You're told the initial Principal is $500, the interest rate is 3%, over 6 years. So you have everything that you need to solve the problem, just plug in the values and solve for A(6)
A(t) = P*e^(rt)
A(6) = 500 * e^(0.03 * 6)
A(6) = 500 * e^(0.18)
A(6) = 500 * 2.71828^(0.18)
A(6) = 500 * 1.19721
A(6) = 598.60861
So $500 invested 6 years ago at 3% would be worth $598.61 today.
