99.9+999.9+9999.9=100-0.1+1000-0.1+10000-0.1=11100-0.3=11099.7供参考
99.9+999.9+9999.9=100+1000+10000-0.1*3=11100-0.3=11099.7
100-0.1+1000-0.1+10000-0.1=11100-0.3=11099.7