A piece of string is 30 cm long. What will be the length of each side if the string is used to form :
an equilateral triangle ?

Answer

To find the length of each side of an equilateral triangle formed by a 30 cm long piece of string, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Problem**: We have a string that is 30 cm long, and we want to form an equilateral triangle with it. In an equilateral triangle, all three sides are of equal length.

2. **Identify the Perimeter**: The total length of the string represents the perimeter of the equilateral triangle. Therefore, the perimeter \( P \) of the triangle is given as:
\[ P = 30 \text{ cm} \]

3. **Use the Formula for Perimeter of an Equilateral Triangle**: The formula for the perimeter \( P \) of an equilateral triangle with side length \( s \) is:
\[ P = 3 \times s \]

4. **Set Up the Equation**: We can set up the equation using the perimeter:
\[ 3 \times s = 30 \]

5. **Solve for Side Length \( s \)**: To find the length of one side, divide both sides of the equation by 3:
\[ s = \frac{30}{3} \]

6. **Calculate the Value**: Now, perform the division:
\[ s = 10 \text{ cm} \]

7. **Conclusion**: Therefore, the length of each side of the equilateral triangle is:
\[ s = 10 \text{ cm} \]

### Final Answer:
The length of each side of the equilateral triangle is **10 cm**.