What is the approximate volume of a tree trunk if the trunk is 12 feet tall with a circumference of 4.5 feet? A. 29.40 ft3 B. 21.17 ft3 C. 19.54 ft3 D. 25.92 ft3

Respuesta :

Answer:

Option C is correct

[tex]19.54 ft^3[/tex]

Step-by-step explanation:

Assume that the truck is in cylindrical shape with uniform circumference.

Circumference(C) of the trunk is given by:

[tex]C = 2 \pi r[/tex]                    .....[1]

where, r is the radius of the trunk.

Volume of the cylinder(V) is given by:

[tex]V = \pi r^2h[/tex]                  .....[2]

where, r is the radius and h is the height of the tree trunk.

As per the statement:

If the trunk is 12 feet tall with a circumference of 4.5 feet

⇒ h = 12 feet and C = 4.5 feet

From equation [1], we have;

[tex]4.5 = 2 \pi r[/tex]

Divide both sides by [tex]2 \pi[/tex]

[tex]r  = \frac{4.5}{2 \pi}[/tex]

Substitute in [2] we have;

[tex]V = \pi \cdot (\frac{4.5}{2 \pi})^2 \cdot 12[/tex]

Use [tex]\pi = 3.14[/tex]

⇒[tex]V= \frac{12 \cdot 4.5 \cdot 4.5}{4 \cdot 3.14}[/tex]

Simplify:

[tex]V \approx 19.54 ft^3[/tex]

Therefore, the approximate volume of a tree trunk is, [tex]19.54 ft^3[/tex]