this an example problem of mixture problem in algebra
since the total amount of the container is 3.2, and let x be the amount of the solution to be withdrawn.
So the amount of the solution left is (3.2 – x), it also the amount of the 100 % solution.
0.354(3.2 – x) + 1*(3.2 – x) = 3.2*(0.733)
Solving for x = 1.47 liters is withdrawn