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2 years ago

I’m struggling so much please help

Mathematics

2 answers:

Ann [662]2 years ago

8 0

Answer:

Cone volume:

$v=\frac{1}{3} \pi r^{2} h=\frac{1}{3} \pi (\frac{12}{2})^{2} (14)=168\pi$

Cylinder volume:

$v=\pi r^{2} h=\pi (4)^{2} (3)=48\pi$

Volume of wood:

$V=v(cone)-v(cylinder)=168\pi -48\pi =120\pi cm^{3}$

Hope this helps

7nadin3 [17]2 years ago

5 0

Answer:

see explanation

Step-by-step explanation:

The volume (V) of wood used is calculated as

V = volume of cone - volume of cylinder

V = $\frac{1}{3}$ πr²h - πr²h

diameter of cone = 12, so radius = 12 ÷ 2 = 6

V = $\frac{1}{3}$ π × 6² × 14 - π × 4² × 3

= $\frac{1}{3}$ π × 36 × 14 - π × 16 × 3

= π × 12 × 14 - 48π

= 168π - 48π

= 120π cm³

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