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The radius of a circle whose circumference is equal to the sum of the circumferences of the two circles of diameters 36 cm and 20 cm is

(A) 56 cm   (B) 42 cm   (C) 28 cm   (D) 16 cm

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Question 11 The radius of a circle whose circumference is equal to the sum of the circumferences of the two circles of diameters 36 cm and 20 cm is (A) 56 cm (B) 42 cm (C) 28 cm (D) 16 cm Now, Circumference of 18 cm circle + Circumference of 10 cm circle = Circumference of circle with radius r 2𝜋(18) + 2𝜋(10) = 2𝜋r 18 + 10 = r 28 = r r = 28 cm So, the correct answer is (C)

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.