Question

The height and radius of a right circular cone are 24 cm and 7 cm respectively. The slant height of the cone is:

• A. 24 cm
• B. 31 cm
• C. 26 cm
• D. 25 cm

Answer 1

The Correct Option is D

The slant height \(l\) of a right circular cone can be calculated using the Pythagoras theorem, as it forms a right triangle with the height and radius:

\[ l = \sqrt{r^2 + h^2} \]

Substitute the given values \(r = 7 \, \text{cm}\) and \(h = 24 \, \text{cm}\):

\[ l = \sqrt{7^2 + 24^2} = \sqrt{49 + 576} = \sqrt{625} = 25 \, \text{cm} \]

Thus, the slant height is 25 cm.