Question

From the data given below state which group is more variable A or B?

Answer 1

Let assumed mean `A=45` and `h=10` For group A

Variance `sigma^(2)=h^(2)[(sumf_(i)d_(i)^(2))/N-((sumf_(i)d_(i))/N)^(2)]`
`=10^(2)[342/150-((-6)/150)^(2)]`
`=100[(51300-36)/(150xx150)]`
`=51264/225=227.84`
For group B

Variance `sigma^(2)=h^(2)[(sumf_(i)d_(i)^(2))/N-((sumf_(i)d_(i))/N)^(2)]`
`=10^(2)[366/100-((-6)/150)^(2)]`
`=100[(54900-36)/(150xx150)]`
`=54864/225=243.84`
`:.` The variance of group B is more
`:.` The data of group B is more variable.