1d Kinematics, missing something.

[Kildars]

A person who walks for exercise produces the position-time graph given with this problem.

(b) Calculate the average velocity for each segment to verify your answers to part (a).
A
m/s
B
m/s
C
m/s
D
m/s

B is obviously 0

For A I did .20 of an hour is 300 seconds.
And 1km = 1000m

So 1000/300 =3.33 and that is wrong..

What am I doing wrong here I used:
$$v_{ave} = \Delta x / \Delta t$$

 

[radou]

The expression for average velocity is correct, but you calculated the time wrong. 1 hour equals 3600 seconds. So, 0.2 hours equals 720 seconds.

 

[Kildars]

Ah, thank you.

I corrected my mistake and fixed my answers and they're correct.