The curved surface area of a hemisphere is 27 | vedclass

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(B) The formula for the curved surface area $(CSA)$ of a hemisphere is $2 \pi r^2$.Given $CSA = 27.72 	ext{ cm}^2$.$2 	imes \frac{22}{7} 	imes r^2

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$2.1$

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(B) The formula for the curved surface area $(CSA)$ of a hemisphere is $2 \pi r^2$.Given $CSA = 27.72 	ext{ cm}^2$.$2 	imes \frac{22}{7} 	imes r^2 = 27.72$$r^2 = \frac{27.72 	imes 7}{44} = 0.63 	imes 7 = 4.41$$r = \sqrt{4.41} = 2.1 	ext{ cm}$.To verify with volume: The formula for the volume $(V)$ of a hemisphere is $\frac{2}{3} \pi r^3$.$V = \frac{2}{3} 	imes \frac{22}{7} 	imes (2.1)^3 = \frac{2}{3} 	imes \frac{22}{7} 	imes 9.261 = 44 	imes 0.441 = 19.404 	ext{ cm}^3$.Since both conditions are satisfied,the radius is $2.1 	ext{ cm}$.

The curved surface area of a hemisphere is $27.72 \text{ cm}^2$ and its volume is $19.404 \text{ cm}^3$. Find its radius in $\text{cm}$.

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