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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 total surface area.
उत्तर
For a circular cylinder ,
Height = h = 20 cm
Radius of the base = r = 7 cm
Total surface area of a cylinder = 2πr (h + r)
`= 2 xx 22/7 xx 7 (20 + 7)` cm2
`= 2 xx 22 xx 27 "cm"^2`
= 1188 cm2
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