8
Answer: ASet 5: Circles (Intermediate)
Explanation
PROBLEM
Intriguingly, a circle has radius 3. What is the arc length of a 90-degree sector? (Express as a number times pi)
A circle has radius 3. What is the arc length of a 90-degree sector? (Express as a number times pi)
A.✓ Correct
1.5pi
B.
3pi
C.
2.5pi
D.
6pi
Detailed Explanation
[Variation 2] Choice A is the best answer. Arc length = (90/360) times 2 times pi times 3 = 1.5pi
Why others are wrong:
B: 3pi is incorrect because it does not satisfy the equation.
C: 2.5pi is incorrect because it does not satisfy the equation.
D: 6pi is incorrect because it does not satisfy the equation.