Answer:
D) Standard deviation is 5.41
Step-by-step explanation:
We are given
count N = 9
Sum ∑xi = 113
Mean = ∑xi /N = 12.55
Standard deviation = [tex]\sqrt{ \frac{(summation xi-mean)^2}{N} - (mean)^2 }[/tex] where i = 1 to 9
upon substituting the values we get
Standard deviation = [tex]\sqrt{29.277}[/tex] = 5.41