Question

Daphne has a rope that is 60 meters long. She wants to use it to mark the boundary of a circle whose radius is an integer. What's the largest possible radius for her circle, in meters?

Answer 1

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Answer:

9 m

Explanation:

The relationship between radius and circumference is ...

C = 2πr

Daphne wants r an integer such that ...

60 m ≥ 2πr

r ≤ (60 m)/(2π)

r ≤ (30/π) m ≈ 9.549 m

The largest integer radius Daphne can use is 9 meters.