Nqa hnyav: T=(E plus Z) / MxN
T=hnyav nqa los ntawm txhua tus caster
E=qhov hnyav ntawm txoj kev thauj
Z=qhov hnyav ntawm qhov khoom txav
M=tus naj npawb ntawm cov khoom siv tau zoo ntawm lub log
N= yam kev nyab xeeb, feem ntau siv 1.3 ~ 1.5
(Qhov tseem ceeb ntawm qhov chaw thiab qhov hnyav tsis sib xws yuav tsum raug txiav txim siab)
