Division or multiplication a ratio factors by a common factor results in an equivalent ratio. Thus, equivalent ratios to 20 / 15 include: (20/5) / (15/5) = 4 / 3, (20 x 1.2) / (15 x 1.2) = 24 / 18, (20 x 2) / (15 x 2) = 40 / 30. Therefore, three equivalent ratios to 20 / 15 are: 4 / 3, 24 / 18, 40 / 30 etc
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