6.RP.A.2

Understand the concept of a unit rate $a/b$ associated with a ratio $a:b$ with $b \neq 0$, and use rate language in the context of a ratio relationship. For example, “This recipe has a ratio of $3$ cups of flour to $4$ cups of sugar, so there is $3/4$ cup of flour for each cup of sugar.” “We paid $\$75$ for $15$ hamburgers, which is a rate of $\$5$ per hamburger.”*