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प्रश्न
In Fig. 5, is a decorative block, made up two solids – a cube and a hemisphere. The base of the block is a cube of side 6 cm and the hemisphere fixed on the top has diameter of 3.5 cm. Find the total surface area of the bock `(Use pi=22/7)`
उत्तर
Surface area of the block = Total surface area of the cube − Base area of the hemisphere + Curved surface area of the hemisphere
=6×(Edge)2−πr2+2πr2
=(63+πr2)
`=(216+22/7xx3.5/2xx3.5/2)`
=(216+9.625)
=225.625 cm2
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