The radius of two concentric circles is in the ratio 2:5, then find out the ratio between their areas.

Thanks you very much for your question. Your questions was – The radius of two concentric circles is in the ratio 2:5, then find out the ratio between their areas. According to the question, the radius of two concentric circles is in the ratio 2:5. The standard formula to calculate the area of a circle (A) = Πr2, where r is the radius of the circle. Since, p is a constant, we can say that A is directly proportional to the square of the radius. ∴ A1 : A2 = r12 : r22 = (2)2 : (5)2 = 4 : 25 Hence, the correct answer is option c. Hope you understand this Math question. if you have more questions then Ask here. You can also visit my website: http://knowledgeworldbd.com Find me on facebook, twitter & Google Plus