Answer:
139.13 m/min or 2.319 m/s
Step-by-step explanation:
You want Eric's average speed if he ran 4 laps on a 400 m track with lap times of 2, 3, 3, and 3.5 minutes.
Average speed
The relationship between speed, time, and distance is ...
s = d/t
s = (4·400 m)/(2 +3 +3 +3.5 min) = 1600/11.5 m/min ≈ 139.13 m/min
We conventionally see speed written in km/h or m/s. A second is 1/60 of a minute, so Eric will have run 1/60 of 139.13 m in one second.
(139.13 m/min) × (1 min)/(60 s) = 139.13/60 m/s ≈ 2.319 m/s
Eric's average speed was about 139.13 m/min, or 2.319 m/s.
