Question

The ratio of the radius and the height of a cylinder is 3:2.The radius is 21 cm. Find it's CSA,TSA and volume

Answer 1

cylinder:

r:h=3:2

21:h=3:2

h = 21x2/3 = 14cm

CsA =2πrh=2x22x2: Ix14/7=1848cm2. Ans

TSA =I848+2πr 2

= l848+2x22x21^2/7

= 4620cm2. Ans

VOL= πr 2 h

= 22x21 ^2 x 14/7=19404cm3... Ans.

Answer 2

$\large\underline\pink{Given:-}$

Cylinder of Height = 4 cm

Cylinder of Radius = 3.5 cm

$\large\underline\pink{To find:-}$

Fine the ratio of the TSA and CSA of a cylinder ....?

$\large\underline\pink{Solutions:-}$

$\: \: \: \: \: \therefore \: \: Total \: \: surface \: \: area \: \: cylinder \: \: = \: \: {2} \: \pi \: r \: {({r} \: + \: {h})}$

$\: \: \: \: \: \leadsto \: \: {2} \: \times \: \frac{22}{7} \: \times \: {3.5} \: {({3.5} \: + \: {4})}$

$\: \: \: \: \: \leadsto \: \: {2} \: \times \: \frac{22}{7} \: \times \: {3.5} \: \times \: {7.5}$

$\: \: \: \: \: \leadsto \: \: {2} \: \times \: {22} \: \times \: {0.5} \: \times \: {7.5}$

$\: \: \: \: \: \leadsto \: \: {44} \: \times \: {3.75}$

$\: \: \: \: \: \leadsto \: \: {165} \: {cm}^{2}$

$\: \: \: \: \: \therefore \: \: Curved \: \: surface \: \: area \: \: of Cylinder \: \: = \: \: {2} \: \pi \: r \: h$

$\: \: \: \: \: \leadsto \: \: {2} \: \times \: \frac{22}{7} \: \times \: {3.5} \: \times \: {4}$

$\: \: \: \: \: \leadsto \: \: {2} \: \times \: {22} \: \times \: {0.5} \: \times \: {4}$

$\: \: \: \: \: \leadsto \: \: {44} \: \times \: {2}$

$\: \: \: \: \: \leadsto \: \: {88} \: {cm}^{2}$

$\: \: \: \: \: Ratio \: \: = \: \: \frac{TSA \: \: of \: \: Cylinder}{CSA \: \: of \: \: Cylinder}$

$\: \: \: \: \: \leadsto \: \: \frac{165}{88}$

$\: \: \: \: \: \: \: Hence, \\ \: \:\therefore \: \: The \: \: ratio \: \: of \: \: the \: \: TSA \: \: and \: \: CSA \: \: of \: \: a \: \: cylinder \: \: {165} \: : \: {88}$