Difficulty: Easy
Correct Answer: 162
Explanation:
Introduction / Context:
Perimeter of a semicircle consists of the semicircular arc plus the straight diameter edge. Recognizing this avoids the common mistake of using only the curved length.
Given Data / Assumptions:
Concept / Approach:
Full circumference is 2 * pi * r. Half of that is pi * r. Therefore P = pi * r + D. Using pi = 22/7 works neatly with multiples of 7.
Step-by-Step Solution:
Verification / Alternative check:
Compute half circumference as (pi * D)/2 + D = (22/7 * 63)/2 + 63 = (198)/2 + 63 = 99 + 63 = 162 cm. Same result confirms consistency.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
162
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