Answer:
Coefficient of skewness = 0.5785
Population standard deviation = 88.154
Step-by-step explanation:
Given the data:
Month Jan Feb Mar Apr May Jun Jul
Unit Sales 314 285 158 482 284 310 281
Reordered data : 158, 281, 284, 285, 310, 314, 482
The population mean of the data :
Mean, μ = Σx / n = 2114 / 7 = 302
The median :
1/2(n+1)th term
n = 7
1/2(8)th term
Median = 4th term = 285
The population standard deviation, s :
s = √(Σ(x - μ)²/n)
s = √[(158-302)^2 + (281-302)^2 + (284-302)^2 + (285-302)^2 + (310-302)^2 + (314-302)^2 + (482-302)^2] / 7
s= √(54398 / 7)
s = √7771.1428
s = 88.154
The Pearson Coefficient of skewness :
[3(μ - median)] / s
3(302 - 285) / 88.154
3(17) / 88.154
51 / 88.154
= 0.5785