If the circumference of a circle and the perimeter of a square are equal, then

(A) Area of the circle = Area of the square

(B) Area of the circle > Area of the square

(C) Area of the circle < Area of the square

(D) Nothing definite can be said about the relation between the areas of the circle and square.

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Transcript

Question 5 If the circumference of a circle and the perimeter of a square are equal, then (A) Area of the circle = Area of the square (B) Area of the circle > Area of the square (C) Area of the circle < Area of the square (D) Nothing definite can be said about the relation between the areas of the circle and square. Let Radius of circle = r Side of square = a Now, given that Circumference of Circle = Perimeter of Square 2𝜋r = 4a 𝜋r = 2a 2a = 𝜋r a = 𝝅/𝟐 𝒓 Now, we need to find relation between Area of square and circle Area of circle = 𝜋𝑟^2 Circle Area of circle = 𝝅𝒓^𝟐 Square Area of square = a2 = (𝜋/2 𝑟)^2 = 𝝅^𝟐/𝟒 𝒓^𝟐 Since 𝝅𝒓^𝟐 > 𝜋^2/4 𝑟^2 Therefore, Area of the circle > Area of the square So, the correct answer is (B)

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.