Question

Find the area of a circle whose radius is 7 cm.

Hint:

Remember: Area of a circle is found by using \( A = \pi r^2 \). First square the radius, then multiply by \( \pi \).

Answer 1

Step 1: Write the formula for area of a circle.}
The formula for the area of a circle is \[ A = \pi r^2 \]
Step 2: Identify the given radius.}
Here, the radius of the circle is \[ r = 7 \, \text{cm} \]
Step 3: Substitute the value in the formula.}
Putting \( r = 7 \) cm in the formula, we get \[ A = \pi \times 7^2 \]
Step 4: Simplify the expression.}
Since \[ 7^2 = 49 \] therefore, \[ A = \pi \times 49 \]
Step 5: Find the final answer.}
Using \( \pi = \frac{22}{7} \), we get \[ A = \frac{22}{7} \times 49 = 154 \, \text{cm}^2 \] So, the area of the circle is \[ \boxed{154 \, \text{cm}^2} \]