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Territorial Army Paper I : Official Practice Test Paper - 4

Option 4 : 14 (2/7) km/h

**Given:**

Columbus covered 3 journeys of 200 km, 300 km and 500 km with a speed of 40 km/h, 20 km/h and 10 km/h respectively.

**Formula used:**

Average speed = Total distance/Total time

**Calculations:**

Total distance covered by him = 200 + 300 + 500 = 1000 km

Total time taken by him = (200/40) + (300/20) + (500/10) = 70 hours

Average speed = Total distance/total time taken

⇒ 1000/70

⇒ 14(2/7) km/h

**∴ Option 4 is the correct choice.**