A train travels 300 km in 3 hours, then 200 km in 2.5 hours. What is its average speed?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Aptitude & Reasoning conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Average speed is total distance divided by total time, not the average of the two speeds.
Total distance = 300 + 200 = 500 km.
Total time = 3 + 2.5 = 5.5 hours.
Average speed = 500 / 5.5 ≈ 90.91 km/h.
Common trap: averaging 100 km/h and 80 km/h gives 90, which is wrong because the time spent at each speed differs.
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