7th: Recognize and represent proportional relationships between quantities. Compute unit rates associated with ratios of fractions, including ratios of lengths, areas and other quantities measured in like or different units.
8th: Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion, which repeats eventually into a rational number. 8.NS.2 Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions.
