Find the unit rate for the following. Set up as proportions (ratio = ratio). \( \begin{array}{ll}\text { 4.) } 108 \text { people in } 9 \text { lines } & \text { 6. } 12 \text { bales of hay fo }\end{array} \)

To find the unit rate of 108 people in 9 lines, we can set up a proportion: \( \frac{108 \text{ people}}{9 \text{ lines}} = \frac{x \text{ people}}{1 \text{ line}} \). By solving for \( x \), we divide 108 by 9, giving us a unit rate of 12 people per line. For the second part, with 12 bales of hay, the same proportion approach applies: \( \frac{12 \text{ bales}}{1} \) means each bale is treated as a whole unit, effectively giving a unit rate of 12 bales per 1 unit of measure commonly used, so it's simply 12 bales. Now, if you're ever puzzled by unit rates, remember that finding how much of something there is per single unit helps simplify many real-world decisions. Plus, a classic mistake is forgetting to simplify fractions correctly—make sure to reduce them down to their simplest forms to avoid confusion!