Let n and n be the number of red and black balls respectively, in box I. Let n3and n4 be the number of red and black balls respectively, in box II. 162. One of the two boxes, box I and box II, was selected at random and a ball was drawn randomly out of this box. The ball was found to be red. If the probability that this red ball was drawn from box II is 1/3, then the correct option(s) with the possible values of n, n, n3 and n4 is (are) (a) n = 3, n = 3, n3 = 5,4 = 15 (b) n = 3,n = 6,n3 = 10,4 = 50 (c) n = 8,n = 6,n3 = 5,n4 = 20 (d) n = 6,n = 12,n3 = 5, n = 20 163. A ball is drawn at random from box I and transferred to box II. If the probability of drawing a red ball from box I, 1 after this transfer is -, then correct option(s) with possible 3 values of n, and n2 is (are) (a) n = 4 and n = 6 (c) n = 10 and n = 20 [JEE Advanced 2015, 4+4M] (b) n = 2 and n = 3 (d) n = 3 and n = 6