Mathematics for IGCSE & O level - Probability (Section 1 - No. 13)
In a bag with 6 red balls and 4 black balls. What is the probability of selecting 2 black balls, if the ball is not replaced?
2/9
2/15
8/45
1/2
설명
P(black then black) = (4/10)*(3/9) = 12/90 = 2/15.