Assertion : Perimeter of the regular hexagon with side 7 cm is 42 cm.
Reason : Perimeter of a n-sided regular closed figure = `n xx` [length of one side]

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true and reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If assertion is false but reason is true.

Answer

To solve the question, we need to evaluate the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that the perimeter of a regular hexagon with a side length of 7 cm is 42 cm.

### Step 2: Calculate the Perimeter of the Hexagon
A regular hexagon has 6 equal sides. The formula for the perimeter \( P \) of a regular polygon is given by:
\[ P = n \times \text{(length of one side)} \]
where \( n \) is the number of sides.

For a hexagon:
- \( n = 6 \)
- Length of one side = 7 cm

Using the formula:
\[ P = 6 \times 7 \]
\[ P = 42 \text{ cm} \]

### Step 3: Verify the Assertion
The calculation shows that the perimeter of the hexagon is indeed 42 cm. Therefore, the assertion is correct.

### Step 4: Understand the Reason
The reason states that the perimeter of an n-sided regular closed figure is calculated as \( n \times \text{(length of one side)} \).

### Step 5: Validate the Reason
This statement is a general formula for calculating the perimeter of any regular polygon, including a hexagon. Since we used this formula to calculate the perimeter of the hexagon, the reason is also correct.

### Conclusion
Both the assertion and the reason are correct. The assertion correctly states the perimeter of the hexagon, and the reason correctly explains how to calculate the perimeter of any regular polygon.

### Final Answer
Both the assertion and the reason are correct, and the reason is the correct explanation for the assertion.

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