A box contains four red balls and eight black balls. Two balls are randomly chosen from the box, and are not replaced. Let event B be choosing a black ball first and event R be choosing a red ball second.
Answer
P(B) =:
8/12
P(R | B) =:
4/11
P(B ∩ R) =:
8/33
The probability that the first ball chosen is black and the second ball chosen is red is about percent.: