If two balls are randomly selected from a green urn containing 6 black and 6 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?
Select:
A) A.2/9	B) B.4/9	C) C.5/9	D) D.1/3	E) E.5/22
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) = 6/12   Probability(second ball is white) = 5/11   Probability (both balls are white) = (6/12)*(5/11) = 5/22   Answer E.5/22
<result>E</result>
If two balls are randomly selected from a green urn containing 6 black and 6 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?