There are 20 tiles in a bag. of these, 9 are purple, 5 are black and the rest are white. event a= drawing a white tile on the first draw event b= drawing a black tile on the second draw if two tiles are drawn from the bag one after the other not replaced, what is p(b|a) expressed in simplest form? a. 1/4 b. 5/19 c. 3/10 d. 9/20