Question

find the height,lateral surface and whole surface of cylinder whose radius is 7cm and volume is 330 cm²

Answer 1

height = 2.1428571429
lateral surface = 92.4
whole surface = 400.4

Answer 2

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\therefore{\text{Height\:of\:cylinder=2.14\:cm}}}$

$\green{\therefore{\text{C.S.A\:of\:cylinder=94.16\:cm}^{2}}}$

$\green{\therefore{\text{T.S.A\:of\:cylinder=402.16\:cm}^{2}}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\green{ \underline \bold{Given : }} \\ : \implies \text{Radius(r) = 7\: cm} \\ \\ : \implies \text{Volume\:of\:cylinder=330\: cm}^{3}\\ \\ \red{ \underline \bold{To \: Find : }}\\ : \implies \text{Height\: of \: cylinder(h) = ? }\\\\ :\implies \text{C.S.A\:of\:cylinder=?}\\\\ :\implies \text{T.S.A\:of\:cylinder=?}$

• According to given question :

$\bold{As \: we \: know \: that} \\ :\implies \text{Volume\: of \: cylinder} =\pi r^{2}h \\ \\ : \implies 330= \frac{22}{7} \times 7^{2}\times h \\ \\:\implies330\times7= 154\times h\\ \\ :\implies h=\frac{\cancel{330}}{\cancel{154}}\\\\ \green{:\implies\text{Height\: of \: cylinder=2.14\: cm}}\\\\ \bold{As \: we \: know \: that} \\ : \implies \text{C.S.A\: of \: cylinder} =2\pi rh \\ \\ : \implies \text{C.S.A\: of \: cylinder} =2 \times \frac{ 22}{7} \times 7\times 2.14 \\ \\ : \implies \text{C.S.A\: of \: cylinder} =2 \times 22 \times 2.14 \\ \\ \green{ : \implies \text{C.S.A\: of \: cylinder} =94.16\: {cm}^{2}} \\ \\ \bold{As \: we \: know \: that} \\ : \implies \text{T.S.A\: of \: cylinder} =2\pi r(h + r) \\ \\ : \implies \text{T.S.A\: of \: cylinder} =2 \times \frac{22}{7} \times 7(2.14+ 7) \\ \\ : \implies \text{T.S.A\: of \: cylinder} =2 \times 22\times 9.14 \\ \\ \green{ : \implies \text{T.S.A\: of \: cylinder} =402.16\: {cm}^{2} }$