If two balls are randomly selected from a green urn containing 9 black and 9 white balls and placed into a yellow urn initially containing 5 black and 3 white balls. What is the probability that the yellow urn will contain an equal number of black and white balls after the change?
Options
A) A.2/9 B) B.4/9 C) C.4/17 D) D.1/3 E) E.1/9
To have equal number of black and white balls, the yellow urn must have 5 black and 5 white balls. So the balls we select out of the green urn must be both white.   Probability (first ball is white) = 9/18   Probability(second ball is white) = 8/17   Probability (both balls are white) = (9/18)*(8/17) = 4/17   Answer C.4/17
<result>C</result>
If two balls are randomly selected from a green urn containing 9 black and 9 white balls and placed into a yellow urn initially containing 5 black and 3 white balls. What is the probability that the yellow urn will contain an equal number of black and white balls after the change?