Question

find the curved surface area of cylinder if r=4.2cm , h=14cm​

Answer 1

Given:

• Radius of cylinder = 4.2cm
• Height of cylinder = 14cm

To find:

• Curved surface area of cylinder

Solution:

Given that radius and height of cylinder is 4.2cm and 14cm respectively. Now, in order to find Curved surface area of cylinder,

We know that :

• $\large{\boxed{\bf{Curved\: surface\:area\:of\: cylinder\:=\:2πrh}}}$

Where,

• π = $\dfrac{22}{7}$
• r = radius of cylinder
• h = height of cylinder

Let put given values in formula :

$\large{\sf{CSA\:of\: cylinder\:=\: 2πrh}}$

$:\implies\large{\sf{CSA\:of\: cylinder\:=\: 2×\dfrac{22}{7}×4.2×14}}$

$:\implies\large{\sf{CSA\:of\: cylinder\:=\: 2×{\dfrac{22}{\cancel{7}}×4.2×{\cancel{14}}}}}$

$:\implies\large{\sf{CSA\:of\: cylinder\:=\:2×22×4.2×2}}$

$:\implies\large{\sf{CSA\:of\: cylinder\:=\:369.6}}$

Therefore,

• $\large{\boxed{\bf{\green{CSA\:of\: cylinder\:=\:369.6cm²}}}}$

Answer 2

Solution:-

• Here,The radius of cylinder is 4.2 cm and height of cylinder is 14 cm.So we can use the formula of curved surface areaof cylinder.

Where,

• CSA = Curved surface area
• r = radius
• h = height
• π = 22/7

Putting the values,

$\\ \red{\bigstar}\;\underline{\boxed{\sf{CSA\;of\;cylinder\;=\;2\pi rh \;sq.units}}}$

$\\ \dashrightarrow\;\sf{CSA= 2\times \frac{22}{\cancel{7}}\times 4.2\times \cancel{14}}\\ \\ \dashrightarrow\;\sf{CSA= 2 \times 22 \times 4.2 \times 2}\\ \\ \dashrightarrow\;\sf{CSA = 44 \;\times 8.4}\\ \\ \dashrightarrow\;\sf{CSA = 369.6\;cm^2}$

Hence,

• The CSA of cylinder is 369.6 cm².