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.
根据正态分布标准化的公式(X-μ)/σ进行转化,相当于求P(Z≥3)。———解析中这句话没有理解