Question
Quantitative Aptitude Question on Triangles, Circles & Quadrilaterals
The radii of three concentric circles are in the ratio 2: 3: 4. What is the ratio of sum of areas of two inner circles to the area of the region between outermost circle and innermost circle?
A
12:11
B
13:12
C
15:11
D
10:7
Answer
13:12
Explanation
Solution
The correct option is (B): 13:12.
(Radius of circle)2 ∝ Area of circle
Let OA = 2x, OB = 3x and OC = 4x
Required ratio = (Sum of area of two inner circles): (Area of region between outermost circle and innermost circle)
= [(2x)2 + (3x)2 ]: [(4x)2 - (2x)2 ]
= (4 + 9): (16 - 4)
= 13:12.