The lifetimes of all batteries produced by certain company in a year have a distribution that is symmetric about the mean m. If the distribution has a standard deviation of d, what percent of the distribution is greater than m+d?
(1) 68 percent of the distribution lies in the interval from m-d to m+d, inclusive
(2)16 percent of the distribution is less than m-d
答案是D，题干中给出的标准差这个条件怎么用呀？作者: iRoy 时间: 2010-6-29 17:18
