The equation is 30,000+200x=80,000. X is the number of sales.
It is four. So two and two you add them together to be four. Good job. Your learning :)
<span>The distance from the vertex to the centroid is twice the distance from the centroid to the side.
This means that 3x + 5 = 2 * (2x)
</span><span>3x + 5 = 4x
x = 5
Source:
http://www.1728.org/trictr.htm
</span>
There follows the formula for "z-score:"
raw score - mean
z = ------------------------------
standard dev
9.1 - 8
Here, the z-score is z = ------------- = 0.344
3.2