GRE
The probability that red ball is selected when you add a blue ball to the box
The probability that red ball is selected when you remove a red ball to the box
p+s
ps
$$\frac{2}{3}$$ P(A)
P(B or C)
The probability that event A occurs
0.3
The probability that either G will occur or H will occur, but not both
r+s-r*s
25000 +道题目
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