Question

A train travels 20 km at a uniform speed of 60 km h- and the next 20 km at a uniform speed of 80 km h,
Calculate its average speed.

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Answer 1

A train travels 20km at a uniform speed of 60km/hr and the next 20km at a ... Calculate its average speed. ... 20 + 20 / 20/60 + 20/ 80 ... total distance traveled = 40 km

Answer 2

for 1st

D =20km

S=60km/h

T= D/S

T= 20km/60km/h

t=1/3h

again

t= 20km/80km/h

t= 1/4h

now averagespeed =40/7/12 =68.57 km/s