480 bottles because 300 divided by 5 is 60 so then you multiply 60 by 8 and you get 480!
The prime factorization of 50 is 2x5x5
Sqrt(18x^5y) + sqrt(32xy^3) - sqrt(128xy)
You may separate the roots to produce solvable square roots!
sqrt(9x^4)*sqrt(2xy) + sqrt(16y^2)*sqrt(2xy) - sqrt(64)*sqrt(2xy)
Simplifying makes it ...
(3x^2 + 4y - 8)*sqrt(2xy)
This should be the closest you can get to a simplified equation.
Answer
Let t be number of minutes since tap is opened
water is increased by 20 gallons of water per minute.
sugar increase rate of 3 pounds per minute
water :- W(t) = 350 + 10 t
sugar :- S(t) = 10 + 3 t
concentration
C(t) = 
at t = 15 minutes
C(15) = 
C(15) = 
C(15) = 0.11
at beginning t = 0 minutes
C(0) = 
C(0) = 
C(0) = 0.0286
C(15) > C(0)
hence, concentration is increasing as time is passing.
C
5 is 1/3 of 15 and 1 is 1/3 of 3 so C would be correct