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प्रश्न
The height of a circular cylinder is 20 cm and the radius of its base is 7 cm. Find :
- the volume
- the total surface area.
उत्तर
For circular cylinder,
Height = h = 20 cm
Radius of the base = r = 7 cm
i. Volume of a cylinder = πr2h
= `22/7 xx 7 xx 7 xx 20 cm^3`
= 3080 cm3
ii. Total surface area of a cylinder = 2πr(h + r)
= `2 xx 22/7 xx 7(20 + 7) cm^2`
= 2 × 22 × 27 cm2
= 1188 cm2
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