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Choose the correct alternative answer for the following question.

#### Options

440 cm

^{2 }550 cm

^{2}330 cm

^{2 }110 cm

^{2 }

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#### Solution

Radius of the cone, r = 7 cm

Height of the cone, h = 24 cm

Let l be the slant height of the cone.

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

∴ Curved surface area of the cone = \[\pi r l = \frac{22}{7} \times 7 \times 25\] = 550 cm^{2}

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