Abdul while driving to school, computes the average speed for his trip to be `20 kmh^(-1)`. On his return trip along the same route, there is less traffic and the average speed is `40 kmh^(-1)`. What is the average speed for Abdul's trip ?

Explanation

To find the average speed for Abdul's entire trip, we can follow these steps:

### Step 1: Define the distance
Let the distance from Abdul's home to school be \( s \) kilometers. Therefore, the total distance for the round trip (to school and back) is:
\[ \text{Total Distance} = s + s = 2s \]

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