Answer:
60.15 km
Explanation:
If 6 km on the map represents 4 mi on land, then we'd get the answer by using the relation
6 km -> 4 mi
x km -> 40.1 mi
Where x km is the length on the map we're looking for. If we cross multiply
6 * 40.1 = 4x
240.6 = 4x
x = 240.6/4
x = 60.15 km.
That is the length we're looking for