Answer:
The actual distance is 24 kilometers.
Explanation:
The picture that shows the needed information is attached.
According to the graph, the distance showed between Gendet and Montrose is 1.5cm with a scale of 1 centimeter = 16 kilometers.
This scale means that each centimeter on the paper represents 16 kilometers of the real distance. So, what we need to do is just multiply the 1.5 cm by 16 km, because that's the scale:

Therefore, the actual distance is 24 kilometers.