Home
Class 14
MATHS
What will be the area of a circle whose ...

What will be the area of a circle whose circumference is 132 cm ?

A

`693 cm^(2)`

B

`264 cm^(2)`

C

`5227 cm^(2)`

D

`1386 cm^(2)`

Text Solution

AI Generated Solution

The correct Answer is:
To find the area of a circle whose circumference is given as 132 cm, we can follow these steps: ### Step-by-Step Solution: 1. **Identify the given information**: - The circumference of the circle is given as 132 cm. 2. **Recall the formula for circumference**: - The formula for the circumference (C) of a circle is given by: \[ C = 2 \pi r \] where \( r \) is the radius of the circle. 3. **Set up the equation**: - Since we know the circumference, we can set up the equation: \[ 2 \pi r = 132 \] 4. **Solve for the radius (r)**: - To find \( r \), we can rearrange the equation: \[ r = \frac{132}{2 \pi} \] - Simplifying this gives: \[ r = \frac{66}{\pi} \] 5. **Recall the formula for area**: - The area (A) of a circle is given by: \[ A = \pi r^2 \] 6. **Substitute the value of r into the area formula**: - Now we substitute \( r = \frac{66}{\pi} \) into the area formula: \[ A = \pi \left(\frac{66}{\pi}\right)^2 \] 7. **Calculate \( r^2 \)**: - Squaring \( r \): \[ r^2 = \left(\frac{66}{\pi}\right)^2 = \frac{66^2}{\pi^2} = \frac{4356}{\pi^2} \] 8. **Substitute \( r^2 \) back into the area formula**: - Now substituting back, we have: \[ A = \pi \cdot \frac{4356}{\pi^2} \] 9. **Simplify the area**: - The \( \pi \) in the numerator and one \( \pi \) in the denominator cancel out: \[ A = \frac{4356}{\pi} \] 10. **Calculate the numerical value of the area**: - Using \( \pi \approx 3.14 \): \[ A \approx \frac{4356}{3.14} \approx 1386 \text{ cm}^2 \] ### Final Answer: The area of the circle is approximately **1386 cm²**.
Promotional Banner