What is a mean proportion, medial sum or quantity, made out of unequal sums or quantities; an arithmetical mean. Thus, if A loses 5 dollars, B 9, and C 16, the sum is 30, and the average 10 called?

average — A mean proportion, medial sum or quantity, made out of unequal sums or quantities; an arithmetical mean. Thus, if A loses 5 dollars, B 9, and C 16, the sum is 30, and the average 10. (Webster's 1913.)

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