A particle moving in a straight line covers half the distance with speed of `3 m//s`. The half of the distance is covered in two equal intervals with speed of `4.5 m//s and 7.5 m//s` respectively. The average speed of the particle during this motion is :

Explanation

To solve the problem step-by-step, we will calculate the average speed of the particle during its motion from point A to point C.

### Step 1: Define the total distance
Let the total distance \( D \) be represented as \( x \). Therefore, the first half of the distance is \( \frac{x}{2} \) and the second half is also \( \frac{x}{2} \).

### Step 2: Calculate the time taken for the first half of the distance
The first half of the distance \( \frac{x}{2} \) is covered with a speed of \( 3 \, \text{m/s} \).

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