1. **State the problem:** We need to find how much Camila's company charges per mile more than Juan's company, given Juan's charges are represented by a line passing through points $(0,4)$ and $(10,18)$. 2. **Formula used:** The charge per mile is the slope of the line, calculated by the formula for slope between two points $$(x_1,y_1) \text{ and } (x_2,y_2):$$ $$m = \frac{y_2 - y_1}{x_2 - x_1}$$ 3. **Calculate the slope for Juan's company:** $$m = \frac{18 - 4}{10 - 0} = \frac{14}{10} = 1.4$$ This means Juan's company charges $1.4$ dollars per mile plus a base fee of $4$ dollars. 4. **Interpretation:** The slope $1.4$ is the per mile charge for Juan's company. 5. **Answer:** Camila's company charges $\boxed{1.4}$ dollars per mile more than Juan's company if the problem implies Camila's rate is the slope difference. If more info about Camila's rate is given, subtract Juan's slope from Camila's slope to find the difference. Since only Juan's data is given, the per mile charge for Juan's company is $1.4$ dollars.