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If the radius of circle is 7 cm, then fi...

If the radius of circle is 7 cm, then find the perimeter of a quadrant.

A

25 cm

B

24 cm

C

26 cm

D

27 cm

Text Solution

AI Generated Solution

The correct Answer is:
To find the perimeter of a quadrant of a circle with a radius of 7 cm, we can follow these steps: ### Step-by-Step Solution: 1. **Understand the Quadrant**: A quadrant is one-fourth of a circle. The perimeter of a quadrant consists of two parts: the curved part (which is one-fourth of the circumference of the circle) and the two straight sides (which are the radii of the circle). 2. **Calculate the Circumference of the Circle**: The formula for the circumference \( C \) of a circle is given by: \[ C = 2\pi r \] where \( r \) is the radius. Here, \( r = 7 \) cm. \[ C = 2 \times \pi \times 7 \] 3. **Substitute the Value of \( \pi \)**: We can use \( \pi \approx \frac{22}{7} \) for our calculations. \[ C = 2 \times \frac{22}{7} \times 7 \] 4. **Simplify the Circumference**: \[ C = 2 \times 22 = 44 \text{ cm} \] 5. **Calculate the Curved Length of the Quadrant**: Since a quadrant is one-fourth of the circle, the curved length \( L \) of the quadrant is: \[ L = \frac{1}{4} \times C = \frac{1}{4} \times 44 = 11 \text{ cm} \] 6. **Calculate the Length of the Straight Sides**: The straight sides of the quadrant are the two radii of the circle. Each radius is 7 cm, so the total length of the straight sides is: \[ \text{Total straight sides} = 2 \times r = 2 \times 7 = 14 \text{ cm} \] 7. **Calculate the Total Perimeter of the Quadrant**: Now, we can find the total perimeter \( P \) of the quadrant by adding the curved length and the lengths of the straight sides: \[ P = L + \text{Total straight sides} = 11 + 14 = 25 \text{ cm} \] ### Final Answer: The perimeter of the quadrant is **25 cm**. ---
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