A train travels from station A to B at 60 km/h and returns at 90 km/h. What is the average speed for the whole trip?
Category: Math · Difficulty: expert
Hint: Remember the formula for average speed: total distance divided by total time.
Answer
72 km/h
Explanation
Average speed = 2 * (speed1 * speed2) / (speed1 + speed2) = 2 * (60 * 90) / (60 + 90) = 72 km/h.
This is a expert math riddle — one of the harder riddles here. The answer is 72 km/h.
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