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If the circumference of a circle is 3 cm...

If the circumference of a circle is 3 cm, then its area, in `cm^(2)`, is

A

`(9pi)/(4)`

B

`(3pi)/(2)`

C

`(9)/(4pi)`

D

`(4)/(9pi)`

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The correct Answer is:
To find the area of a circle when its circumference is given, we can follow these steps: ### Step-by-Step Solution: 1. **Identify the given information**: The circumference of the circle is given as 3 cm. 2. **Use the formula for circumference**: The formula for the circumference (C) of a circle is: \[ C = 2\pi r \] where \( r \) is the radius of the circle. 3. **Set up the equation**: Substitute the given circumference into the formula: \[ 3 = 2\pi r \] 4. **Solve for the radius \( r \)**: Rearranging the equation to isolate \( r \): \[ r = \frac{3}{2\pi} \] 5. **Use the formula for area**: The area (A) of a circle is given by: \[ A = \pi r^2 \] 6. **Substitute the radius into the area formula**: Substitute \( r = \frac{3}{2\pi} \) into the area formula: \[ A = \pi \left(\frac{3}{2\pi}\right)^2 \] 7. **Calculate \( r^2 \)**: \[ A = \pi \cdot \frac{9}{4\pi^2} \] 8. **Simplify the expression**: \[ A = \frac{9\pi}{4\pi^2} \] Cancel out one \( \pi \): \[ A = \frac{9}{4\pi} \text{ cm}^2 \] ### Final Answer: The area of the circle is \( \frac{9}{4\pi} \) cm².
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