Question

plzzzzz solve it... ​

Answer 1

$\large{\red{\bold{\underline{Given:}}}}$

$\sf \: Radius \: of \: the \: cylinder = 35cm \\ \\ \sf \: Height \: of \: cylinder = 35cm$

$\large{\green{\bold{\underline{To \: Find:}}}}$

$\sf \: (i) \: Total \: surface \: area \: of \: cylinder \\ \\ \sf \: (ii) \: Curved \: surface \: area \: of \: cylinder$

$\large{\blue{\bold{\underline{Formula \: Used:}}}}$

$\sf \: Total \: surface \: area = 2\pi r(r + h) \\ \\ \sf \: Curved \: surface \: area = 2\pi rh$

$\large{\red{\underline\bold{{Solution:}}}}$

$\sf \: Let \: the \: radius \: of \: the \: cylinder \: be \: r, \\ \sf \: and \: the \: height \: of \: the \: cylinder \: as \: h$

$\large{\green{\bold{\underline{Then:}}}}$

$\sf \: (i) \: Total \: surface \: area = 2\pi r(r + h) \\ \\ \rightarrow \: \sf Total \: surface \: area = 2 \times \frac{22}{7} \times 35(35 + 35) \\ \\ \rightarrow \: \sf Total \: surface \: area = 2 \times \frac{22}{7} \times 35(70) \\ \\ \rightarrow \: \sf \: Total \: surface \: area = \frac{44}{\cancel7} \times \cancel35 \times 70 \\ \\ \rightarrow \: \sf \: Total \: surface \: area = 15400 \: {cm}^{2}$

$\large{\pink{\bold{\underline{Now:}}}}$

$\sf \: (ii) \: Curved \: surface \: area = 2\pi rh \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 2 \times \frac{22}{7} \times 35 \times 35 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 2 \times \frac{22}{\cancel7} \times \cancel35 \times 35 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 44 \times 5 \times 35 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 7700 \: {cm}^{2}$

$\large{\orange{\bold{\underline{Therefore:}}}}$

$\sf \: The \: total \: surface \: area \: of \: cylinder \: is \\ \sf \: 15400 {cm}^{2} \: and \: curved \: surface \: area \: is \: 7700 {cm}^{2}.$

Answer 2

$\large{\red{\underline\bold{{Solution:}}}}$

$\sf \: Let \: the \: radius \: of \: the \: cylinder \: be \: r, \\ \sf \: and \: the \: height \: of \: the \: cylinder \: as \: h$

$\large{\green{\bold{\underline{Then:}}}}$

$\sf \: (i) \: Total \: surface \: area = 2\pi r(r + h) \\ \\ \rightarrow \: \sf Total \: surface \: area = 2 \times \frac{22}{7} \times 35(35 + 35) \\ \\ \rightarrow \: \sf Total \: surface \: area = 2 \times \frac{22}{7} \times 35(70) \\ \\ \rightarrow \: \sf \: Total \: surface \: area = \frac{44}{\cancel7} \times \cancel35 \times 70 \\ \\ \rightarrow \: \sf \: Total \: surface \: area = 15400 \: {cm}^{2}$

$\large{\pink{\bold{\underline{Now:}}}}$

$\sf \: (ii) \: Curved \: surface \: area = 2\pi rh \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 2 \times \frac{22}{7} \times 35 \times 35 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 2 \times \frac{22}{\cancel7} \times \cancel35 \times 35 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 44 \times 5 \times 35 \\ \\ \rightarrow \: \sf \: Curved \: surface \: area = 7700 \: {cm}^{2}$