Question

3. Abdul, while driving to school,
computes the average speed for his tell
20 kmh '. on his return trip
same route, there is less
traffic and the average speed is 30kmh.
What is the average speed for Abdul's trip?

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Answer 1

Answer:

Abdul, while driving to school, computes the average speed for his trip to be 20 km h-1. On his return trip along the same route, there is less traffic and the average speed is 30 km h-1.

Explanation:

The distance Abdul commutes while driving from Home to School = s

Let us assume time taken by Abdul to commutes this distance = t1

Distance Abdul commutes while driving from School to Home = S

Let us assume time taken by Abdul to commutes this distance = t2

Also we know that

The time taken from Home to School t1=S/v1av

Similarly Time taken from School to Home t2=S/v2av

Total distance

Total distance from home to school and backward = 2S——-(i)

Total time taken from home to school and backward (T)=S/20+S/30———-(ii)

Formula

Speed = Distance / Time

Therefore,

Average Speed(Vav)for covering total distance (2s)=Total Distance/Total Time

So from equations (i) and (ii) we get,

Average Speed(Vav) =2S/(S/20+S/30)

=2S/[30S+20S)/600] =1200S/50S

=24kmh-1

Final Answer

The average speed for Abdul’s trip = 24kmh-1