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Question
The diameter of a cylinder is 28 cm and its height is 20 cm. The total surface area of the cylinder is
Options
2993 cm2
2992 cm2
2292 cm2
2229 cm2
Solution
2992 cm2
The total surface area of the cylinder = 2 πr + 2r2
= 2pi (h + r)
`= [2xx22/7xx14xx(20+14)]"cm"^2` `["d" = 28 cm => "r" = 28/2 "cm" = 14 "cm" ]`
`= 20944/7 "cm"^2`
= 2992 cm2
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