A car moves from A to B with a speed of ...

A car moves from A to B with a speed of 30 kmph and from B to A with a speed of 20 kmph. What is the average speed of the car ?

25 kmph

24 kmph

50 kmph

10 kmph

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The correct Answer is:

`v_("avg") = (2v_(1)v_(2))/(v_(1) + v_(2)) = (2 xx 30 xx 20)/(30 + 20) = 24` kmph

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