1. Given that the population data is : 15,5,8,2,5
• number of sample in data , ,n = 5
,• Mean = sum of sample in the data / number of sample
= (15+5+8+2+5)/5
= 35/5
Therefore mean = 7
2. Calculate varience as in the box below:
[tex]\begin{gathered} _{}\text{Varience = }\frac{1}{n}\mleft\lbrace(x_i-\vec{x}\mright)^2 \\ \text{ = }\frac{1}{5}\mleft\lbrace(7-15)^2+(7-5)^2+(7-8)^2+(7-2)^2+(7-5)^2\mright\rbrace \\ \text{ = }\frac{1}{5}\mleft\lbrace(-8^2\mright)+(-2)^2+(-1^2)+(5^2)+(2^2)\} \\ \text{ =}\frac{1}{5}\mleft\lbrace64\text{ + 4+ 1 +25+4}\mright\rbrace \\ \text{ = }\frac{1}{5}(98) \\ \text{ = }\frac{98}{5} \\ \therefore S\tan dard\text{ deviation = }\sqrt[]{varience\text{ }} \\ \text{ = }\sqrt[]{\frac{98}{5}}\text{ } \\ \text{ =4.427} \end{gathered}[/tex]• This means that Standard deviation = 4.43