Probability please help :)

Question

There are 4 red, 2 white, and 2 blue marbles In an urn. Two marbles are slected at random without replacement. What is the probability that neither is red, given that neither is white?

Answer 1

prob that neither is red given neither is white

is the same as

prob that 1st is blue or white given the first is not white and

prob that 2nd is blue or white given the 2nd is not white

which is

prob that the first is blue and the second is blue = 2/8 X 1/7 = 2/56 = 1/28