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rule of three

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Definition of rule of three

: a rule in mathematics: the product of the means in a proportion equals the product of the extremes —used for finding the fourth term of a proportion where three are given

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rule of three

rule of thumb

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“Rule of three.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rule%20of%20three. Accessed 4 Dec. 2021.

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