列竖式计算下面各题,带△号的要验算.12.7+6.9= 20.5﹣7.6= 78×69=434÷7= 906÷3= △843÷6=验算:
5+3= 5-3= 6-6= 8+1= 9+1= 10-4=
6-5= 10-5= 4+3= 2+2= 2+1= 6-5=
8+2= 7-5= 7+2= 10-10= 9-9= 1+1=
10-3= 6+1= 9+1= 8-3= 9-6= 4+3=
5-5= 6+0= 7-7= 4+0= 9+0= 10-9=