Question

Find the volume of cone whose
Diameter = 20 cm
Height = 100 mm
take $\pi$ as 3.14

Note - Kindly watch the question properly

Answer 1

$\Large{\bf{\green{\mathfrak{\dag{\underline{\underline{Given:-}}}}}}}$

• Diameter = 20 cm

• Height = 100 mm

$\Large{\bf{\orange{\mathfrak{\dag{\underline{\underline{To \: Find:-}}}}}}}$

• Volume of the Cone

$\Large{\bf{\red{\mathfrak{\dag{\underline{\underline{Solution:-}}}}}}}$

• Height of the cone = 100 mm

• Converting the given units into cm,

• 10 mm $\longrightarrow$ 1 cm

• 100 mm $\longrightarrow$ x cm

• x cm = $\sf \dfrac{100 \: * \: 1}{10}$

• x cm = $\sf \dfrac{10\cancel{0}}{1\cancel{0}}$

• x cm = $\sf \dfrac{10}{1}$

Height of the cone = 10 cm.

• Diameter of the cone = 20 cm.

• Radius = ?

• Radius = $\sf \dfrac{Diameter}{2}$

• Radius = $\sf \dfrac{20}{2}$

• Radius = $\sf \dfrac{\cancel{20}}{\cancel{2}}$

• Radius = $\sf \dfrac{10}{1}$

Radius of the cone = 10 cm.

• Volume of the cone = ?

$\boxed{\pink{\sf Volume \: of \: the \: cone \: = \: \dfrac{1}{3} \pi r^{2} h \: units^{3}}}$

• Substituting the values,

$\sf Volume \: of \: the \: cone \: = \: \dfrac{1}{3} \: * \: 3.14 \: * \: 10^{2} \: * \: 10 \: cm^{3}$

$\sf Volume \: of \: the \: cone \: = \: \dfrac{1}{3} \: * \: 3.14 \: * \: 100 \: * \: 10 \: cm^{3}$

$\sf Volume \: of \: the \: cone \: = \: \dfrac{1}{3} \: * \: 3.14 \: * \: 1000 \: cm^{3}$

$\sf Volume \: of \: the \: cone \: = \: \dfrac{1}{3} \: * \: 3140 \: cm^{3}$

$\sf Volume \: of \: the \: cone \: = \: \dfrac{3140}{3} \: cm^{3}$

• Therefore,

• $\underline{\boxed{\therefore{\blue{\sf Volume \: of \: the \: cone \: = \: 1,046.66 \: cm^{3}.}}}}$

$\Large{\bf{\purple{\mathfrak{\dag{\underline{\underline{More \: Information:-}}}}}}}$

• LSA of a cone = πrl units²

• TSA of a cone = πr (r + l) units²

• Volume of a cone = $\sf \dfrac{1}{3} \pi r^{2} h \: units^{3}$

Answer 2

Given :-

Diameter = 20 cm

Height = 100 mm

To Find :-

Volume of cone

Solution :-

We know that

Radius = Diameter/2

Radius = 20/2

Radius = 10 cm

And

1 cm = 10 mm

100 mm = 100/10 = 10 cm

So,

$\sf Volume_{(cone)} = \dfrac{1}{3} \times \pi \times r^2h$

$\sf Volume =\dfrac{1}{3} \times 3.14 \times 10^2 \times 10$

$\sf Volume = \dfrac{1}{3} \times 3.14 \times 100\times 10$

$\sf Volume = \dfrac{1}{3} \times 314 \times 10$

$\sf Volume = \dfrac{1}{3} \times 3140$

$\sf Volume = 1046.66 \; cm^3$