1. Proportion Ratio: A comparison of two numbers or two like quantities by division Rate: A ratio that compares quantities of different units Equivalent Ratios: Two ratios that are equal Proportion: An equation which states that two ratios are equivalent (Once you have the two equivalent ratios, you’ve formed a proportion)

2. Means of a proportion-The two middle terms in the ratios of a proportion Extremes of a proportion-The first and last terms in the ratios of a proportion. A:B = C:D or a/b = c/d b,c are the means and a,d are the extremes 12/x = 3/2 3x = 24 3x/3 = 24/3 x = 8

3. Percents Percent-A number expressed in relation to 100; represented by the symbol % Base-A number that is multiplied by a rate or of which a percentage or fraction is calculated Rate-A number out of 100 written as a % In the problem 8% of 24, 24 is the base and 8% is the rate