Answer:
 365.85 Minutes
Solution:
 According to statement the rate of drops from faucet is,
 R = 41 Drops / 1 Minute
And 1 Gallon can be filled by 15000 drops. Therefore, the time for filling 1 Gallon volume by 15000 drops is calculated as,
 41 Drops fall in = 1 Minute
So,
 15000 Drops will fall in = X Minutes
Solving for X,
  X  = (15000 Drops × 1 Minute) ÷ 41 Drops
  X  = 365.85 Minutes