Measures of Central Tendency

Arithmetic Mean

A=x1+x2+x3+···+xnn=xii=1nn    xi

Geometric Mean

G=x1·x2·x3·····xnn=i=1nxin    xi0

Harmonic Mean

H=n1x1+1x2+1x3+···+1xn=ni=1n 1xn    xi >0

Quadratic Mean

Q=x12+x22+x32+···+xn2n    xi 0
Keywords: arithmetic mean, geometric mean, harmonic mean, quadratic mean