Two buses, X and Y, both had an average speed of 50 km/h
Two buses, X and Y, both had an average speed of 50 km/h. Daksh says this means both took the same time for their journeys. His mother says not necessarily. Who is right?
Who do you think is right? Pick one.
The answer: His mother is right, the time also depends on the distance — a longer route at the same speed takes longer
Why
Daksh is treating average speed as if it fixes the journey time by itself, but time depends on TWO things — the average speed and the distance covered. Time is distance divided by speed, so two buses at the same average speed take the same time only if they also travelled the same distance. Test it: bus X covers 100 km at an average of 50 km/h, taking 2 hours; bus Y covers 150 km at the same average of 50 km/h, taking 3 hours — identical average speed, different journey times, because the distances differ. His mother is right: the same average speed does not mean the same time — you also need to know the distance each bus covered.
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