A tank contains 3660 ml of water. All the water is poured into 2 containers, x and y, in the ratio 4:11 respectively. What is the capacity of Tank y?

The total ratio representing the water in the containers is 4+11 = 15

Since the ratio representing Tank y is 11, then the capacity of Tank y is 11/15*3660 = <<11/15*3660=2688>>2688 ml. Answer: \boxed{2688}.