NO.PZ2015120604000106
问题如下:
For a normally distributed random variable, the probability that random varible is greater than three standard deviations excess the mean is:
选项:
A.
0.0013.
B.
0.0228.
C.
0.9987.
解释:
A is correct.
1 - F(3) = 1 - 0.9987 = 0.0013.
为什么就等于是求X-μ≥3σ的概率?X-μ是什么