[（8-2x）*0.4+（x+3）*0.36+x*0.35]/11=0.385
（3.2-0.8x+0.36x+1.08+0.35x）/11=0.385
3.2-0.8x+0.36x+1.08+0.35x=4.235
-0.09x=-0.045
x=0.5