Explanation:

Length of the road = 1.01 km = 1010 m
101 plants are planted at equal distance from each other. So, there will be 100 gaps between those plants.
Length of each gap = 1010/100 = 10.1 m
Now, there must be 4 gaps between 5 consecutive plants.
So, required distance = 4 × 10.1 = 40.4 m