Question

The mean score of 25 observations is 80 and the mean score of another 55 observations is 65 determine the mean score of the whole set of observations

Answer 1

Hi there!

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What is Mean?

The average of a given set of numbers is called the Arithmetic mean, or simply the mean, of the given numbers.

Mean = $\frac{Sum \: of \: observations }{Number \: of \: observations }$

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