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प्रश्न
A cylinder of same height and radius is placed on the top of a hemisphere. Find the curved
surface area of the shape if the length of the shape be 7 cm.
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उत्तर
Given length of the shape - 7cm
But length -r +r
⇒ 2r -7 cm
⇒ r - `7/2` cm
⇒ r-3.5 cm
Also : h - r
Total S.A of shape - `2πrh + 2πr^2 - 2πr × r +2πr^2`
- `2πr^2 + 2πr^2`
- `4 πr^2`
- `4× 22/7 × (3.5)^2`
-154`cm^2`
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