# physics

A train travel 20km at a uniform speed 60km/1hr and the next 20km at a uniform speed of 80km/1hr calculate its average speed

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1. avgspeed=distance/time

time= 20/60 + 20/80 hrs=1/3 + 1/4 hr
= 7/12 hr

distance=40 km

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👨‍🏫
bobpursley
2. 126

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3. 68 . 57

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4. yes 68.57 is correct but i want the solution also

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