The answer to the solution is:
X= 7
Slope of AD = (2k - 0)/(2j -b - 0) = 2k/(2j - b)
slope of BC = (2k - 0)/(2j - b) = 2k / (2j - b)
AD ║ BC (same slope)
Slope of AB = 0
Slope of DC = 0
AB║DC
The mean is calculated by adding up all of the data points and then dividing the sum by the amount of points added.
The mean fitness score was 3.2 points. If all of the students scored the same thing (3.2 points) then this would be the fitness score of each student.
Thus, the answer is D. 3.2 points.
I am pretty sure it is 0.064. Hope this helps