10x - 5 + 6x - 12
Collect like terms
(10x + 6x) + (-5 - 12)
<u>16x - 17</u>
The problems associated with choosing appropriate sampling units and frame are given below;
1. The only aid available to the forester or researcher is a map of the farm.
2. Appropriate sampling units will be hard to choose because farm trees are only characterized by attributes such as
- type of crop/plant (as all trees of a certain crop are much likely to have similar width or diameter)
- height of tree (as height is closely related to width)
- location of tree on the farm (e.g. North on the map, East on the map, South on the map, West on the map)
- age of tree (as older trees are more likely to have diameters exceeding 12 inches, than the younger trees)
3. Appropriate frame (size) of sample will be hard to choose because a number of trees cannot just be selected from the total number of trees, if the categorization for sampling units is uncertain.
x = -4