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If the numerical value of the circumfere...

If the numerical value of the circumference and area of a circle is same, then the area is

A

`6pi` sq. unit

B

`4 pi` sq. unit

C

`8 pi` sq. unit

D

`12 pi` sq. unit

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The correct Answer is:
To solve the problem, we need to find the area of a circle when the numerical values of its circumference and area are equal. ### Step-by-Step Solution: 1. **Understand the formulas**: - The formula for the circumference (C) of a circle is given by: \[ C = 2 \pi r \] - The formula for the area (A) of a circle is given by: \[ A = \pi r^2 \] 2. **Set the circumference equal to the area**: Since the problem states that the numerical values of the circumference and area are the same, we can set the two equations equal to each other: \[ 2 \pi r = \pi r^2 \] 3. **Simplify the equation**: We can divide both sides of the equation by \(\pi\) (assuming \(\pi \neq 0\)): \[ 2r = r^2 \] 4. **Rearrange the equation**: Rearranging gives us: \[ r^2 - 2r = 0 \] 5. **Factor the equation**: Factoring out \(r\) gives: \[ r(r - 2) = 0 \] 6. **Solve for \(r\)**: This gives us two solutions: \[ r = 0 \quad \text{or} \quad r = 2 \] Since \(r = 0\) does not represent a valid circle, we take \(r = 2\). 7. **Calculate the area**: Now that we have the radius, we can find the area: \[ A = \pi r^2 = \pi (2)^2 = 4\pi \] ### Conclusion: Thus, the area of the circle is \(4\pi\) square units.
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