• Percent–  A fraction or ration in which the denominator is 100.
• Proportion– An equation which states that two ratios are equal.
• Rate–   A comparison of two quantities that have different units of measure.
• Ratio– Something that compares quantities that share a fixed, multiplicative relationship.
• Rational Number– A number that can be written as a/b where a and b are integers, but b is not equal to 0.
• Unit Ratio– Ratios written as some number to 1.
• Quantity–   An amount that can be counted or measured.

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