A body wlaks to his school at a distance of `6 km ` with constant speed of ` 2-5 km h^(-1)` and walks bach with a constant speed of ` 4 km h^(-1)~ What is avetage speed for the round trip in km h^(-1)` ?

Explanation

To find the average speed for the round trip, we need to follow these steps:

### Step 1: Calculate the time taken to walk to school
The distance to school is 6 km, and the speed while going is 2.5 km/h.

Using the formula:
\[
\text{Time} = \frac{\text{Distance}}{\text{Speed}}
...