The length of a rectangular hall is 4 metres less than 3 times the breadth of the hall. What is the length, if the breadth is b metres?

Answer

To find the length of the rectangular hall based on the given information, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Variables:**
- Let the breadth of the hall be \( b \) meters.

2. **Understand the Relationship:**
- According to the problem, the length of the hall is described as "4 metres less than 3 times the breadth."
- This means we need to express the length in terms of the breadth.

3. **Set Up the Equation:**
- "3 times the breadth" can be written as \( 3b \).
- "4 metres less than this" means we subtract 4 from \( 3b \).
- Therefore, we can express the length \( L \) as:
\[ L = 3b - 4 \]

4. **Final Expression:**
- The length of the rectangular hall in terms of the breadth \( b \) is:
\[ L = 3b - 4 \]