3
Answer: CSet 5: Circles (Intermediate)
Explanation
PROBLEM
Recent studies show that a circle has radius 7. What is the arc length of a 120-degree sector? (Express as a number times pi)
A circle has radius 7. What is the arc length of a 120-degree sector? (Express as a number times pi)
A.
7pi
B.
5.666666666666666pi
C.✓ Correct
4.666666666666666pi
D.
14pi
Detailed Explanation
[Variation 1] Choice C is the best answer. Arc length = (120/360) times 2 times pi times 7 = 4.666666666666666pi
Why others are wrong:
A: 7pi is incorrect because it does not satisfy the equation.
B: 5.666666666666666pi is incorrect because it does not satisfy the equation.
D: 14pi is incorrect because it does not satisfy the equation.