Rajneesh drove his car at a speed of 99 km/h for 2 hours and then he took a rest for one hour. Then, he further drove for 3 hours at a speed of 60 km/h. What was Rajneesh’s average speed (in km/h) during his entire journey?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e 63.
Average speed = Total distance / Total time
First part: 99 km/h × 2 hours = 198 km
Second part: 60 km/h × 3 hours = 180 km
Total distance = 198 + 180 = 378 km
Driving time = 2 + 3 = 5 hours
Rest time = 1 hour
Total time = 5 + 1 = 6 hours
Average speed = 378 ÷ 6 = 63 km/h