a).
Average speed = (distance driven) / (time to drive the distance)
= (255 miles) / (4.75 hours)
= (255/4.75) (mile/hour) = 53.7 miles per hour .
b).
Average velocity =
(displacement) / (time for the trip)
= (distance and direction from
start-point to end-point,
regardless of the route) / (time for the trip)
= (121 miles west) / (4.75 hours)
= (121 / 4.75) (miles per hour west)
= 25.5 miles per hour west .
