[tex]\begin{gathered} \text{The standard deviation for the observed data is given as;} \\ \sigma=\sqrt[]{\frac{\Sigma(x-\mu)^2}{N}} \\ \text{Where }\sigma=s\tan dard\text{ deviation, } \\ x=\text{the values observed (26,26,21,22,20,25,35)} \\ \mu=the\text{ population mean} \\ \text{The mean is derived as } \\ \text{Mean}=\frac{(26+26+21+22+20+25+35)}{7} \\ \text{Mean}=\frac{175}{7} \\ \text{Mean}=25 \\ \Sigma(x-\mu)=(26-25)+(26-25)+(21-25)+(22-25)+(20-25)+(25-25)+(35-25) \\ \Sigma(x-\mu)=1+1+\lbrack-4\rbrack+\lbrack-3\rbrack+\lbrack-5\rbrack+0+10 \\ \Sigma(x-\mu)=1+1-4-3-5+10 \\ \Sigma(x-\mu)=0 \\ \text{Back to the formular;} \\ \sigma=\sqrt[]{\frac{\Sigma(x-\mu)^2}{N}} \\ \sigma=\sqrt[]{\frac{0^2}{7}} \\ \sigma=\sqrt[]{0} \\ \sigma=0 \end{gathered}[/tex]
