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SSC Selection Post 2023 PYQ — Question 59

SSC Selection Post - Matriculation Level - 30 June 2023 - Shift 3 • Quantitative Aptitude • Q59

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The radius of the base of a solid right circular cone is 20 cm, and its height is 21 cm. What is its total surface area (in cm2)?

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Correct answer: B

Explanation

The correct answer is option 2 i.e. 980π.

Radius(r) = 20 cm

height(h) = 21 cm

Slant height (l) = 202+212\sqrt{20^2+21^2} = 841\sqrt{841} = 29 cm

Total surface area = πr(r + l)

⇒ π × 20(20 + 29)

⇒ 20 × 49π = 980π