9
Answer: DSet 1: Circles (Advanced)
Explanation
PROBLEM
A circle has radius 7. What is the arc length of a 90-degree sector? (Express as a number times pi)
A circle has radius 7. What is the arc length of a 90-degree sector? (Express as a number times pi)
A.
14pi
B.
4.5pi
C.
7pi
D.✓ Correct
3.5pi
Detailed Explanation
Choice D is the best answer. Arc length = (90/360) times 2 times pi times 7 = 3.5pi
Why others are wrong:
A: 14pi is incorrect because it does not satisfy the equation.
B: 4.5pi is incorrect because it does not satisfy the equation.
C: 7pi is incorrect because it does not satisfy the equation.