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毛线 · 2019年07月29日

问一道题：NO.PZ2017092702000073 [ CFA I ]

  1. CFA I
  2. Quantitative

问题如下图：

选项：

A.

B.

C.

解释：老师第一步的均值37.75，为什么是加权平均 ，我直接用的算术平均？

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1 个答案

Olive_品职助教 · 2019年07月30日

同学你好，因为sales的三种情况发生概率是不同的，不能直接算数平均，要乘以发生的概率，加油！

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