Question

Volume of a cone is 1212 cm^3
and its height is 24 cm
Find the surface area
of the cone = (pie=22/7)​

Answer 1

Given:

• Volume of cone = 1212cm³

• Height, h = 24 cm

To find out :

Find the surface area of cone.

Formula used:

• Volume of cone = ⅓ × π × r² × h

• Curved surface area = πrl

Solution:

$volume \: of \: cone = \frac{1}{3} \pi \: r {}^{2} h$

$\star \: putting \: the \: values$

$\rightarrow \:1212 = \frac{1}{ \cancel3} \times \frac{22}{7} \times {r}^{2} \times \cancel{ 24} \: {}^{8}$

$\rightarrow1212 \times 7 = 22 \times {r}^{2} \times 8$

$\rightarrow \: {r}^{2} = \frac{1212 \times 7}{176}$

$\rightarrow \: {r}^{2} = 48.20$

$\rightarrow \: r = \sqrt{48 .20}$

$\rightarrow \: r = 6.9429$

✪Curved surface = πrl

Let l cm be the slant height of the cone. Then,

l² = r²+ h²

⇒ l² = (6.94)² + (24)²

⇒ l² = 48.20 + 576

⇒ l² = 624.20

⇒ l = 24.98

Now,

$Curved \: surface \: area = \pi \: rl$

$= \frac{22}{7} \times 6.94 \times 24.98$

$= 696.72$

Answer 2

Given:

• Volume of cone = 1212cm³

• Height, h = 24cm

To find out:

Fine the surface area of cone.

Formula used:

• Volume of cone = 1/3 × π × r² × h

• Curved surface area = πrl

Solutions:

Volume of cone = 1/3 × π × r² × h

1212 = 1/3 × 22/7 × r² × 24

1212 × 7 = 22 × r² × 8

r² = 1212 × 7 / 176

r² = 48.20

r = √48.20

r = 6.9429

Curved surface area = πrl

Let 1cm be the slant height of the cone. then,

1² = r² + h²

1² = (6.94)² + (24)²

1² = 48.20 + 576

1² = 624.20

1² = 24.98

Curved surface area = πrl

22/7 × 6.94 × 24.98

696.72.

silentlover45.❤️