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Answer: ASet 3: Circles (Beginner)
Explanation
PROBLEM
A circle has radius 10. What is its circumference? (Express answer as a number times pi)
A circle has radius 10. What is its circumference? (Express answer as a number times pi)
A.✓ Correct
20pi
B.
100pi
C.
10pi
D.
22pi
Detailed Explanation
Choice A is the best answer. Circumference = 2 times pi times r = 2 times pi times 10 = 20pi
Why others are wrong:
B: 100pi is incorrect because it does not satisfy the equation.
C: 10pi is incorrect because it does not satisfy the equation.
D: 22pi is incorrect because it does not satisfy the equation.