0.9+0.42=53.9﹣5.9=5.4+4.6×5=0.25×4÷0.25×4=4÷3.3=(商用循环小数表示)
10-6= 7-5= 9-2= 10-10= 9-9= 1-1=
4-2= 10-5= 4-3= 2-2= 2-1= 6-5=
6-3= 5-3= 6-6= 8-1= 9-1= 10-4=
8-4= 9-5= 5-5= 3-3= 7-7= 8-7=
9-4= 8-2= 9-7= 4-4= 10-5= 4-2=