Question

During a trip, a driver travelled a distance of 80km at an average speed of 60km/hr.He then changed his speed and travelled the remaining 20km of his journey at 30km/hr. What was the drivers average speed for the entire journey?

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Answer 1

50 km/hr

Explanation:

D = RT

Time for first part of trip = 80/60 = 4/3 hr.

Time for second part of trip = 20/30 = 2/3 hr.

total time for entire trip = 4/3 + 2/3 = 6/3 = 2 hr.

Total distance = 100 km

Average rate of speed for entire trip = 100/2 = 50 km/hr