Pooling Two Group Averages — medium Descriptive Statistics problem | Incognition

Pooling Two Group Averages

20 pts · 20 coins

Descriptive StatisticsMedium

Pooling Two Group Averages

A statistics class of $30$ students sat a single test. Afterwards the results were reported in two groups:

$12$ students had a mean score of $78$
the other $18$ students had a mean score of $88$

What is the mean score of all $30$ students taken together?

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