Question

3 scale up or scale down to determine each unknown quantity.
e $\frac{$40}{15 \text{ gallons}} = \frac{?}{3 \text{ gallons}}$

Explanation:

Step1: Analyze the relationship

We have a proportion \(\frac{\$40}{15 \text{ gallons}}=\frac{?}{3 \text{ gallons}}\). We can find the scale factor by dividing the new gallons by the original gallons. The scale factor \(k=\frac{3}{15}=\frac{1}{5}\).

Step2: Apply the scale factor

To find the unknown amount of money, we multiply the original money by the scale factor. So the unknown quantity \(x = 40\times\frac{1}{5}\).

Step3: Calculate the result

\(40\times\frac{1}{5}=\frac{40}{5} = 8\).

Answer:

\(\$8\)