=0.125*（100+80+0.8）*7.41=（12.5+10+0.1）*7.41=22.6*7.41=20*7.41+2*7.41+0.6*7.41=148.2+14.82+4.446=148.2+15-0.18+4.446=163.02+4.446=167.466
