A swimming pool is 20m long 15m wide and 3m deep. Find the cost of repairing the floor and wall at the rate of Rs. 25per square metre.

Explanation

To find the cost of repairing the floor and walls of a swimming pool that is 20m long, 15m wide, and 3m deep, we will follow these steps:

### Step 1: Calculate the area of the floor
The area of the floor of the swimming pool can be calculated using the formula for the area of a rectangle:
\[ \text{Area of the floor} = \text{Length} \times \text{Width} \]
Given:
- Length = 20 m
- Width = 15 m
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