If the radius of a circle is increased by 100%, the area increases by: MCQ with Answer and Explanation

If the radius of a circle is increased by 100%, the area increases by:
A. 400%
B. 500%
C. 200%
D. 300%
Answer: Option D
Solution (By JKSSB Mock Tests)
Area proportional to radius². New radius 2r, area 4 times, increase = 300% (i.e., 4-1 = 3 times = 300%).

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Percentage Questions

Question #1
If the price of sugar rises by 25%, by what percent must consumption be reduced so that expenditure remains the same?
A. 15%
B. 25%
C. 18%
D. 20%

Correct Answer: Option D


Explanation:
Reduction = (25/125)×100 = 20%.

This question belongs to: Maths Percentage
Question #2
A dishonest dealer sells goods at 10% profit but uses a weight of 800 g for 1 kg. Find his overall profit percent.
A. 32.5%
B. 30%
C. 37.5%
D. 35%

Correct Answer: Option C


Explanation:
CP per g = 1, SP per g = 1.1. For 800 g, CP=800, SP=1000×1.1? Actually, he sells 800 g as 1 kg, so SP for 800 g = price of 1 kg at 10% profit = 1.1 times CP of 1 kg. Let CP of 1 kg = 1000, SP=1100. But he gives only 800 g, so CP=800, SP=1100. Profit = 300, % = (300/800)×100 = 37.5%.

This question belongs to: Maths Percentage
Question #3
60% of a number is 180. The number is:
A. 250
B. 400
C. 300
D. 350

Correct Answer: Option C


Explanation:
0.6x = 180 → x = 300.

This question belongs to: Maths Percentage