A semicircle has a radius of 6.3 cm. What is its perimeter?
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Answer: B. 32.4 cm
Explanation
The perimeter of a semicircle includes both the curved arc length and the straight diameter baseline across the bottom. Multiplying the radius of six point three centimeters by pi plus two gives the total boundary distance. Calculating six point three multiplied by approximately five point one four two eight yields thirty-two point four centimeters. A semicircle represents exactly half of a full circular geometric shape cut along its diameter line. The arc length of a semicircle is calculated by multiplying pi by the radius length. The total perimeter of a closed semicircle always incorporates twice the radius length to account for the flat edge.
Option A proposes thirty-five point four centimeters, overestimating the correct arc and diameter sum. Option C suggests thirty-two centimeters, which lacks the precise decimal precision derived from pi calculations. Option D offers thirty centimeters, underestimating the combined length of the curved arc and straight diameter.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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