A car travels 60 km at 30 km per hour and returns the same distance at 60 km per hour. Its average speed for the whole journey is
- A. 45 km per hour
- B. 40 km per hour
- C. 50 km per hour
- D. 35 km per hour
Explanation
The outward leg takes 2 hours and the return 1 hour, so the total is 120 km in 3 hours, giving 40 km per hour. Averaging the two speeds to get 45 is wrong because more time is spent at the slower speed. Average speed is always total distance divided by total time.
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