Question

find the cylinder whose diameter is 42cm and the area of its curved surface is11880sq.cm
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Answer 1

Answer:

CSA of cylindar= 2"rh

d=42 r=21

2×22/7×21×h

44×3×h

132h

Answer 2

$\bf{\underline{\underline{Question:-}}}$

find the height of cylinder whose diameter is 42cm and the area of its curved surface is 11880 sq.cm

$\bf{\underline{\underline{Given:-}}}$

• Diameter of cylinder is 42cm
• Curved surface area = 11880 sq.cm
• Radius = Diameter/2 = 42/2 = 21cm

$\bf{\underline{\underline{Formula:-}}}$

• Curved surface area of cylinder is 2πrh

$\bf{\underline{\underline{Solution:-}}}$

$\sf \leadsto 11880 = 2 × \frac{22}{7}×21×h$

$\sf \leadsto 11880 = 2×\dfrac{22}{7}×21×h$

$\sf\large \leadsto h = \dfrac{11880}{2×\dfrac{22}{7}×21}$

$\large\sf \leadsto h = \dfrac{11880×7}{2×22×21}$

$\sf \leadsto h= \large\dfrac{11880}{44×3}$

$\sf \leadsto h = \dfrac{11880}{132}$

$\sf \leadsto h = 90cm$

$\bf{\underline{\underline{Hence:-}}}$

• The required height of cylinder is 90 cm