Q16 of 45 Page 11

The height of a right circular cylinder is 10.5 cm. If three times the sum of the areas of its two circular faces is twice the area of the curved surface area. Find the radius of its base.

Given: Height of cylinder = 10.5 cm


To find: radius


Formula Used:


Area of circle = πr2


CSA of cylinder = 2πrh


Explanation:


Height of cylinder = 10.5 cm


Let radius of cylinder = r cm


So,


Area of two bases of cylinder = 2πr2


Area of curved surface of cylinder = 2πrh


According to the question,


3(2× Area of circle) = 2(CSA of cylinder)






Radius of base of cylinder = 7 cm


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