求一道GWD数学

小鱼good · 发表于 2010-3-22 22:24:22

A certain characteristic in a large population has a distribution that is symmetric about the mean m.If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m +d ?

A.16%

B.32%

C.48%

D.84%

E.92%
XDJM们，没看懂题意啊，帮忙解答一下吧

切尔西 · 发表于 2010-3-22 23:49:00

你的答案怎么四个红的，一个黑的，答案该是D的吧？

cindytim · 发表于 2010-3-23 02:14:31

帮顶，也想知道

tracyforever · 发表于 2010-3-23 11:20:51

求教！

slickdeals · 发表于 2010-3-23 11:41:32

A certain characteristic in a large population has a distribution that is symmetric about the mean m.If 68 percent of the distribution lies within one standard deviation d of the mean, what percent of the distribution is less than m +d ?

The distribution is a symmetric about the mean. 68% between m+d and m-d. Therefore the distribution of everything >m+d and <m-d is 32%.
The distribution less than m+d is 68% + 32%/2.

求一道GWD数学

所属分类: GMAT考试

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