Subject: General Aptitude · Chapter: Area · Exam: 2008 · Marks: · Difficulty:
The radii of three concentric circles are in the ratio 1 : 2 : 3. Find the ratio of the area between the two inner circles to that between the two outer circles.
Answer
Answer (as printed):
Explanation
Let the radii of the three concentric circles be r, 2r and 3r respectively. \ Required ratio = p[(2r)2 – r2] : p[(3r)2 – (2r)2] = 3pr2 : 5pr2 = 3 : 5.
Explanation as extracted from the printed page; notation may be imperfect.