A man drives to a town at 20 km/h and returns by the same road at 30 km/h. His average speed for the whole journey is:

  1. 20 km/h
  2. 28 km/h
  3. 24 km/h
  4. 25 km/h
Answer

C) 24 km/h

For equal distances, average speed = dfrac2xyx+y = dfrac2 20 3050 = 24 km/h (not the simple average 25).

Quantitative Reasoning MCQ · More Speed, Time, Work & Ages MCQs · Practise