Question

You drive your car from home at an

average velocity of 80 km/h for 3 h.
Halfway to your destination, you develop
soine engine problems, and for 5 h you
nurse the car the rest of the way. What is
your average velocity for the entire trip?

Answer 1

60 km/h

Step-by-step explanation:

In the first part of the trip, the speed is

v = 80 km/h

while the time interval is

t = 3 h

So, the distance covered is:

d = vt = (80)(3)= 240 km

The problem states that this distance is half distance between home and the destination - so, the total distance between home and the destination is

`D=2d=2(240)=480 km`

The time taken to cover the second part of the trip is 5 h, so the total time taken is

T = 3 h + 5 h = 8 h

Therefore, the average velocity for the entire trip is

`v=(D)/(T)=(480)/(8)=60 km/h`