## Geometry: Common Core (15th Edition)

A ratio compares two similar quantities. They are achieved by dividing one quantity by the other quantity. For example, the ratio of 10 to 5 is: 10 $\div$ 5 = $\frac{10}{5}$ 10:5=2:1 A proportion is a statement that two ratios are equal. For example: 10:5=2:1 $\frac{10}{5}$=$\frac{2}{1}$