What is the maximum amount of silver in grams that can be plated out of 3.8L of an AgNO3 solution containing 3.3% Ag by mass?

Question

(Assume that the density of the solution is 1.02g/mL .)

Answer 1

3.3% by mass means 3.3g Ag/100 g solution. The density of the solution is 1.02 g/mL so 3.8L (3,800 mL) has a mass of 1.02 g/mL x 3800 mL = 3876 g.
(x g Ag/3876)*100 = 3.3
x g Ag = approx 128 g. That's an estimate.