Q. 16

# 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.

Answer :

**Given:** Height of cylinder = 10.5 cm

**To find:** radius

**Formula Used:**

Area of circle = πr^{2}

CSA of cylinder = 2πrh

**Explanation:**

Height of cylinder = 10.5 cm

Let radius of cylinder = r cm

So,

Area of two bases of cylinder = 2πr^{2}

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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