A person jogs eight complete laps around a 400-m track in a total time of 15.5 min . A. Calculate the average speed, in m/s.?

3.44 m/s

8x400m=3200m

15.5minx60=930sec

3200m/930sec=3.441m/s

You have no idea because you don't know the physics. Here, learn this.

distance = average speed X time traveled; S = Vavg T.

That's all there is. That's the physics. You go an average speed for some time and you'll cover some distance.

You do it every day when you go to school and back. Your school is S distance away and it takes you T time to get there.

What's your average speed Vavg = S/T. Same deal for this problem.

Vavg = S/T = NC/T = 8*400/(15.5*60) = 3.4409E+00 m/s. ANS.

NOTE Total distance covered is S = NC where N = 8 times around a track that is C = 400 m long. Also 15.5*60 ~ seconds.