The general formula for this type of decay is N=No e^0.01t, where No is the original amount, N is the amount remaining after t days, and that 0.01 represents the daily decay rate.
We start with No=500 mg and let t= 300 days. Then,
N = No e^0.01t becomes N = 500 mg e^(0.01)(300), or N = 500 mg (e^3).
Can you evaluate this on your calculator?
