from math import sqrt

def moyenne(x1,x2,x3,x4,x5):
    m = (x1+x2+x3+x4+x5)/5
    return(m)

def ecart(x1,x2,x3,x4,x5):
    m = moyenne(x1,x2,x3,x4,x5)
    v = ((x1-m)**2+(x2-m)**2+(x3-m)**2+(x4-m)**2+(x5-m)**2)/5
    e=sqrt(v)
    return(e)