Answer:
To solve this problem, we can use the formula for exponential decay:
m = m0(1 - r)^t
where:
m0 = initial mass (300 grams)
r = decay rate (6% per day, or 0.06)
t = time in days
We want to find the mass at the beginning of the 16th day, so t = 15:
m = 300(1 - 0.06)^15
m ≈ 107.4
Therefore, the mass of the radioactive sample at the beginning of the 16th day of the experiment is approximately 107.4 grams.