A person drives a car for 4 hours at the speed of 75 km/h and for the next 6 hours at the speed of 90 km/h. Find the average speed of the car during the entire journey.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 84 km/h.
Distance = Speed × Time
Distance covered in 4 hours at the speed of 75 km/h = 75 × 4 = 300 km
Distance covered in 6 hours at the speed of 90 km/h = 90 × 6 = 540 km
Average Speed = Total Distance/Total Time
Average Speed = (300 + 540)/10 = 840/10 = 84 km/hr