Question:Distance between two stations A and B is 778 km. Hari Mohan covers the journey from A to B at 84 km per hour and return back to A with a uniform speed of 56 km per hour. Find his average speed during the whole journey.
Answer Required average speed = `(2xy)/(x + y)` km/hr. = `(2 xx 84 xx 56)/(84 xx 56)` km/hr. =`((2 xx 84 xx 56)/140)` km/hr =67.2 km/hr
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Distance between two stations A and B is 778 km. Hari Mohan covers the journey from A to B at 84 km per hour and return back to A with a uniform speed of 56 km per hour. Find his average speed during the whole journey.