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Question
A hemispherical bowl is made of steel, 0.25 cm thick. The inner radius of the bowl is 5 cm. Find the outer curved surface area of the bowl.
`["Assume "pi = 22/7]`
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Solution
Inner radius of hemispherical bowl = 5 cm
The thickness of the bowl = 0.25 cm
∴ Outer radius (r) of hemispherical bowl = (5 + 0.25) cm
= 5.25 cm
Outer curved surface area of hemispherical bowl = 2πr2
= `2xx22/7 (5.25 cm)^2`
= `173.25 cm^2`
Therefore, the outer curved surface area of the bowl is 173.25 cm2.
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