A large stand of fir trees occupies 24 hectares. The trees have an average density of 1 tree per 20m squared. A forester estimates that each tree will yield 300 board-feet. Estimate the yield of the stand if one-tenth of the trees are cut. ​

Respuesta :

Answer:

The yield of the stand if one-tenth of the trees are cut is 360000 board-feet.

Step-by-step explanation:

First, let is find the total amount of fir trees that occupies the area of 24 hectares. (1 hectare = 10000 square meters)

[tex]n = \sigma \cdot A[/tex]

Where:

[tex]\sigma[/tex] - Surface density, measured in trees per square meter.

[tex]A[/tex] - Total area, measured in square meters.

Given that [tex]\sigma = \frac{1}{20}\,\frac{tree}{m^{2}}[/tex] and [tex]A = 24\,h[/tex], the total amount of fir trees is:

[tex]n = \left(\frac{1}{20}\,\frac{trees}{m^{2}} \right)\cdot (24\,h)\cdot \left(10000\,\frac{m^{2}}{h} \right)[/tex]

[tex]n = 12000\,trees[/tex]

It is known that one-tenth of the tress are cut, whose amount is:

[tex]n_{c} = 0.1 \cdot n[/tex]

[tex]n_{c} = 0.1 \cdot (12000\,trees)[/tex]

[tex]n_{c} = 1200\,trees[/tex]

If each tree will yield 300 board-feet, then the yield related to the trees that are cut is:

[tex]y = S\cdot n_{c}[/tex]

Where:

[tex]S[/tex] - Yield of the tress, measured in board-feet per tree.

[tex]n_{c}[/tex] - Amount of trees that will be cut, measured in trees.

If [tex]n_{c} = 1200\,trees[/tex] and [tex]S = 300\,\frac{b-ft}{tree}[/tex], then:

[tex]y = \left(300\,\frac{b-ft}{tree} \right)\cdot (1200\,trees)[/tex]

[tex]y = 360000\,b-ft[/tex]

The yield of the stand if one-tenth of the trees are cut is 360000 board-feet.