Question

the base radius of a cylinder is 10.5cm and its height is 20cm.find the curved surface area and the volume of the cylinder.​

Answer 1

Given : The Base Radius of the Cylinder is 10.5 cm and its Height is 20 cm .

To Find : Find the Curved Surface Area

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SolutioN : Let's Apply the Formula to Solve this question . Let's Go :

$\maltese$ Formula Used :

• ${\underline{\boxed{\pmb{\sf{ Curved \; Surface \; Area = 2 \pi rh }}}}}$

Where :

• $\sf{ \pi = \dfrac{22}{7} }$

• r = Radius
• h = Height

$\maltese$ Calculating the CSA :

$\begin{gathered} \qquad \; \dashrightarrow \; \; \sf { CSA = 2 \pi rh } \\ \\ \\ \end{gathered}$

$\begin{gathered} \qquad \; \dashrightarrow \; \; \sf { CSA = 2 \times \dfrac{22}{7} \times 10.5 \times 20 } \\ \\ \\ \end{gathered}$

$\begin{gathered} \qquad \; \dashrightarrow \; \; \sf { CSA = 2 \times \dfrac{22}{7} \times 210 } \\ \\ \\ \end{gathered}$

$\begin{gathered} \qquad \; \dashrightarrow \; \; \sf { CSA = 2 \times \dfrac{22}{\cancel7} \times \cancel{210} } \\ \\ \\ \end{gathered}$

$\begin{gathered} \qquad \; \dashrightarrow \; \; \sf { CSA = 2 \times 22 \times 30 } \\ \\ \\ \end{gathered}$

$\begin{gathered} \qquad \; \dashrightarrow \; \; \sf { CSA = 44 \times 30 } \\ \\ \\ \end{gathered}$

$\begin{gathered} \qquad \; \dashrightarrow \; \; {\underline{\boxed{\pmb{\sf{ Curved \; Surface \; Area = 1320 \; {cm}^{2} }}}}} \; {\pink{\bigstar}} \\ \\ \\ \end{gathered}$

$\therefore \;$ Surface Area of the Cylinder is 1320 cm² .

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Answer 2

$\underline \bold \red{Thanks \: for \: your \: question \: } \\ \\ </p><p>Your \: required \: answer \: : \\ \\ \bold \blue{Given : } \\ \\ = > Radius = 10.5 cm \\ = > Height = 20 \: cm \: \\ \\ \bold\blue{To \: find :} \\ \\ = > Curved \: Surface \: Area \\ \\ </p><p> = > Volume \\ \\ \underline \bold \red{Solution :} \\ \\ CSA \: of \: cylinder : \\ \\ = > 2 \times \frac{22}{ \cancel7} \times \cancel10.5 \times 20 \\ \\ = > 44 \times 20 \times 1.5 \\ \\ = > \underline \bold{1318.8 \: cm ^{2} } \\ \\ \\ \\ Volume \: of \: cylinder : \\ \\ = > \frac{22}{ \cancel7} \times \cancel10.5 {}^{2} \times 20 \\ \\ = > 22 \times 20 \times 1.5 {}^{2} \\ \\ = > \underline \bold{6929.7 \: cm {}^{3} } \\ \\ \\ \\ Therefore \: area = 1318.8 \: cm {}^{2} \\ </p><p>Therefore \: volume = \: 6929.7 \: cm {}^{3} </p><p> \\ \\ \bold\pink{Brainliest \: Please}$