不进位加和不退位减法
13+3= 19-8= 13-2=
5+11= 11-10= 16-4=
7+12= 18-5= 17-1=
16 11 11
16 1 12
19 13 16
11 + 6 = 17 17 - 6 = 11
13+5= 18 18-5=13
5+13=18 18-13=5
?
5 + 5 = 10
?
10 + 3 = 13
17个
?
17 - 4 = 13
13 - 2 + 3 =
11
14
14 - 2 +1 = 13
15 - 4 +3 = 14
16-5+3= 19-10-6= 13-1+5=
15-3+2= 18-4+4 = 16-3+6=
17-2+3= 15-4+5= 19-8+8=
16-1+2= 13+2-0= 15-2+2=
18-4+2= 15-5+7= 8+10-4=
14 3 17
14 18 19
18 16 19
17 15 15
16 17 14
13 14 15 16 17 18 19
17 16 15 14 13 12 11 1018
19 20 3
12 14 9
5 3
4
5
4
3
21
12 4 16