0.999x1.3-0.111x2.7=0.999x1.3-0.111x(9x0.3)=0.999x1.3-0.999x0.3=0.999(1.3-0.3)=0.999
0.999x1.3-0.111x2.7=(0.999/9)x(9x1.3)-0.111x2.7=0.111x11.7-0.111x2.7=0.111x(11.7-2.7)=0.111x9=0.999