SSC CGL 2023 PYQ — Question 56

SSC CGL - 17 July 2023 - Shift 1 • Quantitative Aptitude • Q56

The volume of a cone with a height equal to the radius, and a slant height of 5 cm is:

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Correct answer: D

Explanation

The correct answer is Option 4 i.e. 125π62\frac{125\pi}{6\sqrt2} cm3.

Let's assume the height of the cone h = radius of the cone r = x

Slant height = 5 cm

Slant height = h2+r2\sqrt{h^2+r^2}

⇒ 5 = x2+x2\sqrt{x^2+x^2}

⇒ 5 = x2\sqrt{2}

⇒ x = 5/2\sqrt{2}

Volume of the cone = 1/3 πr2h

⇒ 13π×(52)2×52\frac{1}{3}\pi\times(\frac{5}{\sqrt2})^2\times \frac{5}{\sqrt2}

⇒ 125π62\frac{125\pi}{6\sqrt2} cm3