Question

Find its volume.And the area of the canvas required.Plz solve it quickly​

Answer 1

Step-by-step explanation:

d=10.5

r=10.5/2=105/20

h=3

volume=1/3πr²h

=1/3×22/7×105/20×105/20×3

1×22×105×105×3/3×7×20×20

=11×15×105/10×200

=11×15×52.5/1000

8662.5/1000

=8.6625m²

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l=√r²+h²

=√(21/4)²+3²

=√441/16+9

=√441+144/16

=√585/16 m²

Answer 2

Solution :-

→ Diameter of cone = 10.5m

So,

→ Radius of cone = (Diameter)/2 = (105/20) = (21/4)m.

And,

→ Height of cone = 3m.

Therefore,

→ Volume of cone = (1/3) * π * r² * h

→ Volume = (1/3) * (22/7) * (21/4)² * 3

→ Volume = (22 * 3 * 21) / 16

→ Volume = 86.625 m³ . (Ans.)

Now again,

→ Radius of cone = (21/4)m

→ Height of cone = 3 m .

So,

→ Slant Height of cone = √(Radius² + Height²)

→ Slant Height = √{(21/4)² + 3²} = √(441/16 + 9) = √(441 + 144)/9 = (√585)/3 = (24.18/3) = 8.06 m.

Therefore,

→ CSA of cone = π * radius * slant Height .

→ CSA = (22/7) * (21/4) * 8.06

→ CSA = (22 * 3 * 8.06) / 4

→ CSA = (11 * 3 * 4.03)

→ CSA = 132.99 m³ . (Ans.)