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A vehicle travels 4 km with speed of 3 km/h and another 4 km with speed of 5 km/h, then its average speed is

Asked in JEE Main 30th Jan 2nd Shift 2023 · Distance and average speed

• (1) 3.75 km/h
• (2) 4.25 km/h
• (3) 3.50 km/h
• (4) 4.00 km/h

Step-by-step solution

Why the other options are wrong

• (2) No single slip gives 4.25; the harmonic mean is always below the arithmetic mean, 4.
• (3) No single slip gives 3.50; the answer must sit between 3 and 5 and just under 4.
• (4) Arithmetic mean (3 + 5)/2, right only for equal times.

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