A truck covers 40 km with an average speed of 80km/h. Then it travels another 40 km with an average speed of 40 km/h. The average speed of the truck for the total distanced covered is:

Average speed = 53.33 km/h

Explanation:

Below is the calculation for the average speed:

Given the average speed of for first 40 km = 80km/h

Time taken to cover the first 40 km = Total Distance / average speed

Time taken to cover the first 40 km = 40 / 80 = 0.5 hours

Given the average speed of for next 40 km = 40km/h

Time taken to cover the next 40 km = Total Distance / average speed

Time taken to cover the next 40 km = 40 / 40 = 1 hours

Now the average speed of the tuck to cover total distance:

Average speed = Total distance / Total time

Average speed = (40 + 40) / (0.5 + 1)

Average speed = 53.33 km/h

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