A person jogs eight complete laps around a quarter-mile track in a total time of 13.1 minutes
A)Calculate the average speed, in m/s
B)Calculate the average velocity, in m/s

For part a) I put that a quarter mile = 402.336 meters. I multiplied 402.336*8 (laps)=3218.688meters
and 13.1 minutes = 786 seconds

Then I did: (3218.688m/786s) and got 4.09 m/s. This answer is right according to the online answer.

I do not know how to set up part B. I know that average velocity equals (displacement/time elapsed). How would I find the displacement?? Thank you for any help!

Question

A person jogs eight complete laps around a quarter-mile track in a total time of 13.1 minutes 
A)Calculate the average speed, in m/s
B)Calculate the average velocity, in m/s

For part a) I put that a quarter mile = 402.336 meters. I multiplied 402.336*8 (laps)=3218.688meters
and 13.1 minutes = 786 seconds

Then I did: (3218.688m/786s) and got 4.09 m/s. This answer is right according to the online answer. 

I do not know how to set up part B. I know that average velocity equals (displacement/time elapsed). How would I find the displacement?? Thank you for any help!

shane_b · Answer

Maybe this will help:
$$Speed_{avg}=\frac{distance}{time}$$
$$Velocity_{avg}=\frac{displacement}{time}$$
Looking at both equations you've clearly done part A correctly. In part B you just need to realize that the person's total displacement after running 8 laps is 0m...so Vavg = 0 m/s.