Mountain railway

The railway line's height difference between points A and B is 38.5 meters. Their horizontal distance is 3.5 km. Determine the average climb in permille up the track.

Correct answer:

r =  11 ‰

Step-by-step explanation:

$$\begin{gathered} y=38.5\text{m} \\ x=3.5\text{km}\to \text{m}=3.5\cdot 1000\text{m}=3500\text{m} \\ r=\frac{y}{x}\cdot 1000=\frac{38.5}{3500}\cdot 1000=11‰ \end{gathered}$$

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