Area, SMB-036

Find the surface area of the solid pictured below which is composed of a right cone with a hemisphere attached to the base. Give your answer to the nearest square centimetre. (3 marks)

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\(\ 616\ \text{cm}^2\)

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\(\text{SA (hemisphere)}\)	\(= \dfrac{1}{2} \times 4 \pi r^2\)
	\(= \dfrac{1}{2} \times 4 \pi \times 7^2\)
	\(=307.87…\ \text{cm}^2\)

\(\text{SA (cone)}\)	\(= \pi rl\)
	\(= \pi \times 7 \times 14\)
	\(=307.87…\ \text{cm}^2\)

\(\text{Total SA}\ = 2 \times 307.87… = 616\ \text{cm}^2\ \ (\text{nearest cm}^2) \)