Question

Find the surface area of a closed cylinder of radius of 7cm and height 20cm assume r=22/7
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Answer 1

refer the picture

hope it helps

Answer 2

$\underline{\pink{Dimensions \:of\:a \: closed \: cylinder :}}$

$Radius (r) = 7 \:cm$

$Height (h) = 20 \:cm\: and \: \pi = \frac{22}{7}$

$i) \blue{Curved\:Surface \:area \:of \:the}$

$\blue{ cylinder }= 2\pi rh$

$= 2 \times \frac{22}{7} \times 7 \times 20$

$= 2 \times 22 \times 20$

$= 880 \: square \:cm$

$ii) \orange{ Total \: surface \:area \: of \: the }$

$\orange{ cylinder} = 2\pi r( r+h)$

$= 2 \times \frac{22}{7} \times 7( 7 + 20 )$

$= 2 \times 22 \times 27$

$= 1188 \: square \:cm$

Therefore.,

$i) \blue{Curved\:Surface \:area \:of \:the}$

$\blue{ cylinder }\green{ = 880 \:cm^{2}}$

$ii) \orange{ Total \: surface \:area \: of \: the }$

$\orange{ cylinder} \green { = 1188\: cm^{2}}$

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