0.6+0.3= 1.2-0.4= 12.5-2.5= 7.9-0.9=
1-0.6= 8.6-7= 3.12×100=
99+68= 0.5+0.5= 1.2-0.3=
10-0.8= 3.39+17.61= 1-0.84-0.16=
7.4+(5.6-4)= 3-0.5+2.5= 24.3-(8.5+5.8)=
10-0.09= 3.8+0.12= 0.01+0.1= 1.5×6+1.5×4=