There are certain number of red balls and white balls in an Urn. The probability of picking up a white ball is 1/6 more than that of a red ball. If 6 white balls are added to the Urn the above difference is doubled. If instead, 6 white balls are removed, the probability of picking up a white ball is :
(a) 1/9
(b) 2/9
(c) 4/9
(d) 5/9
