Question

A researcher interested in the disappearance of fallen leaves in a deciduous forest carried out a field experiment that lasted nearly a year. She collected all the leaves from 100 plots scattered throughout the forest. She measured the amount of leaves present in November, May and August. The percentages reflect the number of leaves found, using the November values as 100 percent.

Answer 1

Answer:

Elm:    50 %; 1 %

Hazel: 69 %; 4 %  

Explanation:

Assume the table looked like this.

$\begin{array}{crrr}\textbf{Month} & \textbf{Ash} & \textbf{Elm} &\textbf{Hazel}\\\text{Nov} &\text{4271 g}& \text{3481 g} & \text{1723 g}\\ & 100\, \% & 100\, \%&100\, \%\\\text{May} & \text{2431 g} & \text{1739 g} & \text{501 g}\\& 100\, \% & x \, \% &z \, \%\\ \text{Aug} & \text{1376 g} &\text{35 g} & \text{62 g}\\& 100\, \% & y \, \% & w \, \%\\\end{array}$

To get the percentages for each species for May and August, you divide that month's mass by the November mass and multiply by 100.

$x = \dfrac{\text{1739 g}}{\text{3481 g}} \times 100 \, \% =50 \,\%\\\\y = \dfrac{\text{35 g}}{\text{3481 g}} \times 100 \, \% = 1 \,\%\\\\z = \dfrac{\text{501 g}}{\text{1723 g}} \times 100 \, \% = 69 \,\%\\\\w = \dfrac{\text{62 g}}{\text{1723 g}} \times 100 \, \% = 4 \,\%$

The figure below shows the graphs for ash and elm.