Selected MCQ

Current Question
The circumference of a circle with radius 7 cm is ____.
  • A. 22 cm
  • B. 44 cm
  • C. 49 cm
  • D. 154 cm
Correct Answer: B
Explanation:
2πr = 44 cm.
Related Question 1
Two circles have a radius relation. Area of the square is 196 cm². Find radius.
  • A. 12π
  • B. 16π
  • C. 24π
  • D. 32π
Correct Answer: C
Explanation:
Side=14, radius=7×? → area relation.
Related Question 2
The radius of a semicircle is 6.3 cm. Find its perimeter.
  • A. 35.4 cm
  • B. 32.4 cm
  • C. 32 cm
  • D. 30 cm
Correct Answer: B
Explanation:
Perimeter = πr + 2r.
Related Question 3
The radius of a circle is increased by 1%. By what percent does its area increase?
  • A. 1.01%
  • B. 5.01%
  • C. 3.01%
  • D. 2.01%
Correct Answer: D
Explanation:
Area ∝ r² → increase ≈ 2.01%.
Related Question 4
The perimeter of a semicircle is 144 cm. What is the radius?
  • A. 25 cm
  • B. 28 cm
  • C. 30 cm
  • D. 35 cm
Correct Answer: B
Explanation:
Perimeter = πr + 2r; solving gives r = 28 cm.
Related Question 5
If the radius of a circle is halved, area becomes ____.
  • A. Half
  • B. One-fourth
  • C. Same
  • D. Double
Correct Answer: B
Explanation:
Area ∝ r² → becomes 1/4.