Question

quick review
you can solve some ratio problems by making a table of equivalent ratios and then graphing the pairs of values on a coordinate plane.
example
days of rain 1 2 3 n
days of sun 2 4 6 8
there will be 4 rainy days if there are 8 sunny days.
practice

1. in gym class, the sixth - graders walk 2 laps for every 3 laps they run. if the students run 12 laps, how many laps will they walk? complete the table. then plot the pairs of values on the coordinate plane.

run (laps) 3 6 9 12
walk (laps) 2

Explanation:

Step1: Identify the ratio

The ratio of walk - to - run laps is 2:3.

Step2: Set up proportion for 6 run laps

Let $x$ be the number of walk laps when running 6 laps. The proportion is $\frac{2}{3}=\frac{x}{6}$. Cross - multiply: $3x = 2\times6$, so $3x=12$, and $x = 4$.

Step3: Set up proportion for 9 run laps

Let $y$ be the number of walk laps when running 9 laps. The proportion is $\frac{2}{3}=\frac{y}{9}$. Cross - multiply: $3y=2\times9$, so $3y = 18$, and $y = 6$.

Step4: Set up proportion for 12 run laps

Let $z$ be the number of walk laps when running 12 laps. The proportion is $\frac{2}{3}=\frac{z}{12}$. Cross - multiply: $3z=2\times12$, so $3z = 24$, and $z = 8$.

Answer:

Run (laps)	3	6	9	12