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प्रश्न
Choose the correct alternative answer for the following question.
विकल्प
440 cm2
550 cm2
330 cm2
110 cm2
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उत्तर
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 cm2
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