A uniform seesaw, 5m long, is supported at its centre. A boy weighing 40 kgf sits at a distance of 1 m from the centre of the seesaw.
(i) To which class of lever does it belong ?
(ii) Find where a girl of weight 20 kgf must sit on the seesaw so as the balance the weight of the boy.

Explanation

To solve the problem step by step, we will address both parts of the question.

### Step 1: Identify the Class of Lever
A seesaw is a type of lever. In this case, the seesaw is supported at its center, which acts as the fulcrum. The boy sitting on one side creates a load, while the other side will have the girl sitting to balance it.

**Answer:** The seesaw belongs to Class 1 lever because the fulcrum is located between the load (the boy) and the effort (the girl).

### Step 2: Set Up the Equation for Balancing the Seesaw
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