A car travels 120km East at 45km/hr, then goes West 50km at 70km/hr, then goes East again for time t at 40km/hr. If the average velocity for the entire trip is 30km/hr East, find the time t.
The Attempt at a Solution
time of car traveling East at beginning:
t=d/t 120km/45 kph t = 2.67hr
time of car traveling West
t=d/t 50km/70 kph t = 0.71hr
Now this is where I get stuck. I'm not sure what the next step would be since I'm not given distance for the car traveling East again. The answer is 3.14 hrs. I know a question like this will be on my test tomorrow, so help would be greatly appreciated.