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abdul while driving to school computes the avera...

Question:
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 40 km h^-1. What is the average speed for Abdul’s trip?

Answer:

Case I: While driving to school

Average speed of Abdul’s trip = 20 km/h

Total distance = d

Let total time taken = t1

Speed = Distance / time

20 = d / t₁

t₁ = d / 20…(i)

Case II: While returning from school

Total distance = d

Speed = 30 km/h

Now,total time taken = t₂

Speed = distance / time

30 = d / t₂

t₂ = d / 30 ..... (ii)

Total distance covered in the trip = d + d = 2d

Total time taken, t = Time taken to go to school + Time taken to return to school

= t₁ + t₂

Total time taken = d / 20 + d / 30

= 3d + 2d / 60

= 5d / 60

= d / 12

From equations (i) and (ii),

Average Speed = 120/5

= 24 km/h

Hence, the average speed for Abdul’s trip is 24 km/h.

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Question:
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 40 km h^-1. What is the average speed for Abdul’s trip?

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Question: 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 40 km h-1. What is the average speed for Abdul’s trip?

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Question:
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 40 km h^-1. What is the average speed for Abdul’s trip?