Question

Please help!!! How do I solve questions 4 and 5?

Answer 1

`\large\boxed{4.\ V=(33.64\pi x)/(3)\approx35.21x}\\\boxed{5.\ V=21\ cm^3}`

Explanation:

4.

The formula of a volume of a cone:

`V=(1)/(3)\pi r^2H`

r - radius

H - height

We have

`2r=11.6\to r=5.8,\ H=x`

Substitute:

`V=(1)/(3)\pi(5.8^2)x=(1)/(3)\pi(33.64)x=(33.64\pi x)/(3)`

`\pi\approx3.14`

`V\approx((33.64)(3.14)x)/(3)\approx35.21x`

5.

The formula of a volume of a pyramid:

`V=(1)/(3)BH`

B - base area

H - height

In the base we have the square. The formula of an area of a square with side s:

`A=s^2`

We have

`s=3cm,\ H=7\ cm`

`B=3^2=9\ cm^2`

`V=(1)/(3)(9)(7)=(3)(7)=21\ cm^3`