An equilateral triangular table has three rounds of red cord along its sides. If the length of the cord is 45 cm, find the side of the table.

Answer

To solve the problem of finding the side of an equilateral triangular table given that three rounds of red cord along its sides total 45 cm, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Problem**: We know that the total length of the cord is 45 cm and that it wraps around the sides of an equilateral triangle three times.

2. **Calculate the Perimeter**: Since the cord wraps around the triangle three times, we can express the total length of the cord as:
\[ \text{Total Length of Cord} = 3 \times \text{Perimeter of Triangle} \]
Therefore, we can set up the equation:
\[ 45 \text{ cm} = 3 \times \text{Perimeter} \]

3. **Solve for the Perimeter**: To find the perimeter of the triangle, we divide both sides of the equation by 3:
\[ \text{Perimeter} = \frac{45 \text{ cm}}{3} = 15 \text{ cm} \]

4. **Use the Perimeter to Find the Side Length**: The perimeter \( P \) of an equilateral triangle is given by the formula:
\[ P = 3 \times \text{Side Length} \]
We can set this equal to the perimeter we found:
\[ 15 \text{ cm} = 3 \times \text{Side Length} \]

5. **Solve for the Side Length**: To find the side length, divide the perimeter by 3:
\[ \text{Side Length} = \frac{15 \text{ cm}}{3} = 5 \text{ cm} \]

6. **Final Answer**: Therefore, the side of the equilateral triangular table is 5 cm.

### Summary:
The side of the equilateral triangular table is **5 cm**.