Quadratic mean definition

quadratic mean

(from the article `mean`) ...1, 1, 2, 5, and 7 cm. Their average area is (12 + 12 + 22 + 52 + 72)/5, or 16 square cm, the area of a square of side 4 cm. The number 4 is the ...
Found on http://www.britannica.com/eb/a-z/q/3

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