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332211abc

A certain characteristic in a large population has a distribution that is symmertric about the mean m. if 60% of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m+d?
OG112, 求翻译啊~~ 后面两句完全看不懂啊。。

Jaycandoit

如果60%的分布在一个标准差之内（这个意思是在m-d和m+d中间的数占总体的60%），问小于m+d的数占分布的百分比。