Question

A car makes a 60-km trip with an average velocity of 38.5-km/h in a direction due north. The trip consists of three parts. The car moves with a constant velocity of 25 km/h due north for the first 15 km and 62 km/h due north for the next 32 km. With what constant velocity does the car travel for the last 13-km segment of the trip?

Answer 1

average velocity= total distance/total time

Time for first leg: 15/25 hr
Time for second leg: 32/62
Time for third leg...

total time=60/38.5=you do it.
time for third leg= distance/timethird=
= 13/(totaltime-15/25 - 32/62)

velocity on third leg= 13/time for third