What is indicating one part of two; in the ratio of one to two. Subduple ratio, the ratio of 1 to 2: thus, 3:6 is a subduple ratio, as 6:3 is a duple ratio called?

subduple — Indicating one part of two; in the ratio of one to two. Subduple ratio, the ratio of 1 to 2: thus, 3:6 is a subduple ratio, as 6:3 is a duple ratio. (Webster's 1913.)

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