Question

Help please I need help with this

Answer 1

We know,

`{\qquad { \longrightarrow \pmb {\sf Volume_((Sphere)) = (4)/(3) \pi {r}^(3) }}}`

Here,

• Radius of the sphere is
  `\sf(1)/(2) .`

• We will take the value of π as
  `\sf(22)/(7) .`

⠀

Substituting the values in the formula :

`{ \longrightarrow {\qquad {\sf Volume_((Sphere)) = (4)/(3) * (22)/(7) * {\bigg((1)/(2) \bigg)}^(3) }}}`

`{ \longrightarrow {\qquad {\sf Volume_((Sphere)) = (4)/(3) * (22)/(7) * (1)/(8) }}}`

`{ \longrightarrow {\qquad {\sf Volume_((Sphere)) = ( \cancel4)/(3) * (22)/(7) * (1)/( \cancel8) }}}`

`{ \longrightarrow {\qquad {\sf Volume_((Sphere)) = ( 1)/(3) * (22)/(7) * (1)/( 2) }}}`

`{ \longrightarrow {\qquad {\sf Volume_((Sphere)) = (22)/(3 * 7 * 2) }}}`

`{ \longrightarrow {\qquad {\sf Volume_((Sphere)) = (22)/(42) }}}`

`{ \longrightarrow {\qquad {\bf Volume_((Sphere)) = (11)/(21) }}}`

⠀

Therefore,

• Radius of the sphere is
  `\bf (11)/(21)` units³.

Answer 2

π/6 ≈ 11/21 cubic units

Explanation:

Use the given values in the formula for the volume of a sphere:

V = 4/3πr³

V = (4/3)(22/7)(1/2)³ = 4·22/(3·7·8) = 11/21 . . . . cubic units