Q10 of 80 Page 56

If a train runs at 40 kmph it reaches its destination late by 11 minutes. But if it runs at 50 kmph it is late by 5 minutes only. Find the distance to be covered by the train.

Let the distance covered by the train be x km.

Time delay when speed is 40 kmph = 11 minutes.


Time delay when speed is 50 kmph = 5 minutes.


The difference in time for different speeds = 11 – 5


= 6 minutes.


= hours.


We know that, speed =


∴ Time =


According to the given condition,



⇒ (LCM of 40 and 50 is 200)



⇒ (Multiplying by 200 on both sides)


⇒ x = 20


∴ The distance to be covered by the train is 20 km.


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