Step-by-step explanation:
In order to describe speed of an object, we must describe the average speed of the entire trip. It is equal to the distance moved divided by time taken.
If a person covers a distance of 1 km to the library in 15 minutes, we can find its average speed.
Firstly, we convert 15 minutes to hour, 15 min = 0.25 hours
Now, using formula of speed = distance/time
It means that the average speed of the person is 4 km/h. Hence, the given statement is true.