If the area of a circle is 154 cm 2 , then its perimeter is

(A) 11 cm   (B) 22 cm   (C) 44 cm   (D) 55 cm

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Question 1 If the area of a circle is 154 cm2, then its perimeter is (A) 11 cm (B) 22 cm (C) 44 cm (D) 55 cm Now, Area of circle = 𝜋r2 154 = 𝟐𝟐/𝟕 × r2 154 × 7/22 = r2 7 × 7 = r2 49 = r2 r2 = 49 r2 = 72 r = 7 cm Now, Perimeter = 2𝜋r = 2 × 22/7 × 7 = 2 × 22 = 44 cm So, the correct answer is (C)

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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.