SOLUTION: In a journey of 1000 km a train covers the first 600 km at 60k/m per hour and the remaining distance at 40 kilometre per hour calculate the average speed of the train during the wh

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Question 1121884: In a journey of 1000 km a train covers the first 600 km at 60k/m per hour and the remaining distance at 40 kilometre per hour calculate the average speed of the train during the whole journey
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the train covers the first 600 kilometers at 60 kilometers per hour.

the train covers the second 400 kilometers at 40 kilometers per hour.

rate * time = distance.

for the first 600 kilometers, the formula becomes 60 * time = 600

solve for time to get time = 600 / 60 = 10 hours.

for the last 400 kilometers, the formula becomes 40 * time = 400.

solve for time to get time = 400 / 40 = 10 hours.

the total time for the 1000 kilometers is 10 + 10 = 20 hours.

rate * time = distance becomes rate * 20 = 1000.

solve for rate to get rate = 1000 / 20 = 50 kilometers per hour.

the average speed of the train for the whole journey is 50 kilometers per hour.