A candy company distributes boxes of chocolates with a mixture of creams, toffees, and cordials. Suppose that the weight of each box is 4 pounds, but the individual weights of the creams, toffees, and cordials vary from box to box For a randomly selected box let X and Y represent the weights of the creams and the toffees, respectively, and suppose that the joint density function of these variables is shown below.

f(x,y) = { 3/32xy, 0 ≤ x ≤ 4, 0 ≤ y ≤ 4, x + y ≤ 4
0, elsewhere

Find the probability that in a given box the cordials account for more than 1/3 of the weight.