A circle has area 346.5 cm².\nFind its circumference (in centimetres).

Difficulty: Easy

Correct Answer: 66

Explanation:

Introduction / Context:
Convert area to radius using A = pi * r^2, then compute circumference C = 2 * pi * r. With A given as a multiple compatible with pi = 22/7, exact arithmetic is straightforward.

Given Data / Assumptions:

A = 346.5 cm²; use pi = 22/7.

Concept / Approach:
r^2 = A / pi; then C = 2 * pi * r.

Step-by-Step Solution:

r^2 = 346.5 / (22/7) = 346.5 * 7 / 22 = 110.25r = √110.25 = 10.5 cmC = 2 * (22/7) * 10.5 = 66 cm

Verification / Alternative check:
Back-compute area: pi*r^2 = (22/7)*(10.5)^2 = (22/7)*110.25 = 346.5 cm².

Final Answer:
66

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