Find the mean , mean deviation about the mean , variance and standard deviation for the following data
4,15,14,12,6,8,11

Explanation

Mean of the given data is `barx =(4+15+14+12+6+8+11)/7=70/7=10`
Now
`therefore` mean deviation about mean =`M.D.(barx)=(Sigma|x_i-barx|)/n=24/7=3.43`
Variance : `sigma_x^2=1/nSigma(x_i-barx)^2`
`=102/7=14.57`
Standard deviation : `sigma=sqrt((1/n)Sigma(x_i-barx)^2)`
`=sqrt14.57`=3.82