A bus driver must complete a 240 km trip in 4 hours. If he averages 70 km an hour for the first 3 hours of his trip, how fast must he travel (in km/h) in the last/final hour?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 30.
Given,
Total distance = 240 km
Total time = 4 hour
We know,
Distance = Speed × time
Now,
Distance covered in 3 hours at an average speed of 70 km/h = 70 × 3 = 210 km
Remaining distance = 240 - 210 = 30 km
The remaining distance is covered in 1 hour
Required speed = 30/1 = 30 km/h