And he defined the average in terms of not the sum divided by two, but he chose the geometric mean.

鲍林定义平均并不是,简单相加在除以二，他选择几何平均。

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In fact, there are some very old books that show this as the average, the sum divided by two arithmetic mean, but the modern practice is to use the geometric mean.

事实上，一些很老的书籍上,平均的定义就是算数意义的，总的来说被分为两种算数意义，但现代我们多用几何意义。

麻省理工公开课 - 固态化学导论课程节选