The relationship of distance-time-speed is defined by the formula
d = v × t
d stands for distance, v stands for speed/velocity, t stands for time
From the question, we know that
⇒ v = 3 in/min
⇒ t = 4 hours
t = 4 × 60 minutes
t = 240 minutes
we convert the time to minutes because the speed is in inch/minute
Input the number to the formula
d = v × t
d = 3 × 240
d = 720
The distance covered in four hours is 720 inches