A student has two boxes 'P' and 'Q' which contain some balls of different colors (White, Orange, and Brown). Box 'P' contains 5 white balls, N orange balls, and 7 brown balls while box 'Q' contains (N - 3) white balls, (N - 4) orange balls, and 6 brown balls. Box 'P' contains 2 more orange balls than brown balls. If 2 balls are drawn, 1 from each box then what is the probability that both balls are of different colors with 'white' balls coming out of the box 'Q'?