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The area of circle is seven times the nu...

The area of circle is seven times the numerical value of its circumference. What is the circumference of the circle?

A

616 units

B

132 units

C

88 units

D

Cannot be determined

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The correct Answer is:
To solve the problem, we need to find the circumference of a circle given that the area of the circle is seven times the numerical value of its circumference. Let's go through the steps: ### Step 1: Write down the formulas for area and circumference of a circle. The area \( A \) of a circle is given by the formula: \[ A = \pi r^2 \] The circumference \( C \) of a circle is given by the formula: \[ C = 2\pi r \] ### Step 2: Set up the equation based on the problem statement. According to the problem, the area is seven times the circumference: \[ A = 7C \] Substituting the formulas for area and circumference into this equation gives: \[ \pi r^2 = 7(2\pi r) \] ### Step 3: Simplify the equation. We can simplify the equation by dividing both sides by \( \pi \) (assuming \( \pi \neq 0 \)): \[ r^2 = 7(2r) \] This simplifies to: \[ r^2 = 14r \] ### Step 4: Rearrange the equation. Rearranging the equation gives us: \[ r^2 - 14r = 0 \] ### Step 5: Factor the equation. Factoring out \( r \) from the equation: \[ r(r - 14) = 0 \] This gives us two solutions: \[ r = 0 \quad \text{or} \quad r = 14 \] Since the radius cannot be zero, we take \( r = 14 \). ### Step 6: Calculate the circumference. Now that we have the radius, we can find the circumference using the formula: \[ C = 2\pi r \] Substituting \( r = 14 \): \[ C = 2\pi(14) = 28\pi \] ### Step 7: Approximate the circumference. Using \( \pi \approx \frac{22}{7} \): \[ C = 28 \times \frac{22}{7} = 88 \text{ units} \] Thus, the circumference of the circle is \( 88 \) units.

To solve the problem, we need to find the circumference of a circle given that the area of the circle is seven times the numerical value of its circumference. Let's go through the steps: ### Step 1: Write down the formulas for area and circumference of a circle. The area \( A \) of a circle is given by the formula: \[ A = \pi r^2 \] The circumference \( C \) of a circle is given by the formula: ...
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