20以内三连加减混合口算练习题(227).docx

《20以内三连加减混合口算练习题(227).docx》由会员分享，可在线阅读，更多相关《20以内三连加减混合口算练习题(227).docx（58页珍藏版）》请在淘文阁 - 分享文档赚钱的网站上搜索。

1、3-3 + 12 =7-4+7二10-5 + 11=12 + 17-19=4+8-2二4+2+3=17-5 + 5 =1 + 3 + 10=19-1 + 2=2 + 12-2 =5 + 4 + 11 =19 + 9-17=2+6-7二20-18 + 4=8 + 16-5=15-3-3 =12-9 + 3=19 -13 - 6=7-2-5=3-3+5=9-8 + 15二3 + 15-6=4-2+7二18 + 3-8=18 - 14 + 11=10-4-6=5+6+7=16-1-13 =12 + 13-7=16 + 16-15 =8-1 + 13 =10 + 3 + 1=4-3 + 11=13-9

2、 + 8=11-2 + 3 =17-3 + 1 =7+2+3=13 -4 + 2二16-15 + 11=15-10-2 =10-5 + 6=6-3 + 11=10 + 2 + 2 =5 + 4- 1=20 + 8-18=8-2-6=4+2+8=6 + 12-6=9-5+8=2+3+1=3 + 12-5 =17-8 + 1=18-2-9=1 + 11 + 7=7 + 14-18=3+1+1=19 + 14-18=13-2-2 =15 - 15 + 12=1 + 15 - 1=8+1+2=20 + 5 - 13 =9+1-1=7+8+3=20 + 2 - 20=20-10 + 3 =10 + 2-

3、3 =17 - 11 + 12 =7-5+7二14-1 + 4=16-4-8=4-2 + 17=15-3-2 =11 + 4-15 =9 + 13 - 14=14-3 + 5 =18 - 16 + 17=20 - 20 + 3 =20-2- 16=13 - 11 + 11=7 + 12-4=11 + 12 - 13 =15-10-4=16-9 + 12 =9 + 4- 5二14 + 16-12=5+8-3二11 + 13 - 13 =18-6 + 8二7+8-2二18-9-6=15 + 1 - 11 =11 -5 + 5 =18-10 + 12=20-3-13 =16 + 10-19=7 +

4、10-12 =18-7 + 4二6-1-3=10 + 18-12 =19 + 5 - 14=15 + 1-13 =16-8 + 6=17-4-7=2 + 20-13 =16 + 1 + 3 =6 + 15-2二20-9-3 =1 + 11 + 2 =20 - 14 - 4=11 + 6-12 =16-15 + 6=8-6+7=15-6 + 3 =20-15 + 12 =2+3+8=20-5-15=13 + 1-1 = 16-3-5=14-4 + 5二 7-7 + 19=18-9 + 9=14 + 2 + 2 =2-2 + 15二11 + 16-15 =19-6 + 7=3+5-3=11 + 1

5、1 - 5 =4 + 20-14=2 + 16-2 =13-8 + 13 =20-2-5 =4+5+5=15-1- 10=19-4-8=6-4+9二17-3 + 6=20 + 10-11 =16 + 18-14=11 + 16-9=20 + 4-8二13 + 20-19=15 + 1 + 2 =5+3-7=10 + 9-9二1 + 16-6=1-1 + 14=18 - 10 - 2=2 + 19-12 =14 + 14-20=11-4-3 =14 + 16-15=10 + 14-16=13-8 + 14=14-4-7=11 + 16-20=18-10 + 8=9-3-1二18-3 + 3 =3

6、-3 + 18=14-14 + 9=12-2 + 8=10-8 + 17=16-7 + 9=14-4-9=7+6+4=5+4+1=4 + 3 + 10=5 + 2 - 1=9-3+8=7-1-3=1+4+4=20 -18 - 2=1 + 18-12 =9-7 + 17=17-5-1 =4 + 12 - 16=6-3+1=12-2-5 =18-13 + 1=11-8 + 3 =20 + 5 - 12 =20 -17 + 3 =2 + 19 - 15 =6 + 10 + 1=12-1 + 6=14-1-8=4 + 1 + 10=13 + 3 - 10=6-2-1=11 + 3 - 11=14-14

7、 + 11 =1 + 1 + 12 =17 -15 + 1=14-8 + 9=17-14 + 3 =1 + 20-13 =3-1 + 17=1 + 17 + 1=8-7+7=19-3-9=18 + 13-20=1 + 16 + 1=4 + 11 - 13 =8-5+2=5+1+9=17-10 + 5 =14-2 + 4=10 + 5-3 =20-13 + 4=4+5+7=13 - 11 + 12 =17-8-3 =12 - 11 + 14=20-5 + 2 =1+7+5=5+7+7=6 + 12-4=14-4 + 9=17-3-3 =17-12 + 13 =9-7+3二7+8-3二19-2-

8、17=18 -16 + 6=6 + 14-6= 14-7-1=12-8-4=10-8 + 5=11 -5 + 7= 12-3-6=12-10-2 =20 + 7-16=15-3-8=16 + 3 - 12 =19 - 16 + 1=9 + 12-14=17 - 1 - 11=12 + 4-15 =18 + 10-15=14 + 10-16=19 - 14 + 7二12-5 + 9=18-4-2 =10 -8 + 16=15-6-9=15 + 1 + 1=8 + 12 - 12=19 + 2-4=10 + 17-17=18 -17 + 2 =7 + 17-13 =16-9 + 9=9+3+5=8

9、 + 15 - 18=10 + 5 + 5 =8-4+7二 14-14 + 2 =4 + 14 + 1=5 + 19-12 =2+9+8=8+3+4=13-3-2 =8-8+8二5+3+8=12-9-2 =15-5 + 9=1+4+2=8-1+6=17-4 + 6 二8 + 18-8=17 + 7-11 =15-7 + 1 =19 - 15 + 16=13 -5 + 7=1 + 4 + 11 =8+6-6=1+7+8=5 + 16-10=12-6 + 3=15 - 10 + 14=10 + 8-13 =18 + 20 - 20=15 + 5 - 14=3-2 + 6二19-8 + 5二16-1

10、1-4=10 + 7 + 1=16-5-2 =18 - 18 + 18=8 + 18-11=9-5 + 10=20-19 + 19=8 + 11-9=9 + 15 - 18=3 + 14 + 3 =7-6+5二6+7-5二15 -10 + 7=11 -6 + 4=9-7 + 13 =13 + 6-15 =17 + 14-16=13 + 17-11 =2 + 18-17=12 + 2 + 6=15 + 11-16=20-5-4=8+2+7=9+2+3=20-11 + 2 =6 + 13 - 13 =12 + 3 + 3=3-1+4=4+4+6=10-2-1=19 -19 + 8=16 + 16-

11、14=8-3+5=9 + 17-9=6-6 + 15 =5 + 5 + 10=16-16 + 3 =16 + 16-18=15 - 12 - 3 =6 + 11 + 1=6 + 18-19=15 + 12 - 13 =16-11 + 10=2 + 5 + 11 =9-2-2=17-13 + 12=11 + 3-8=1+2+5=13 + 4-16=18-8 + 9=18-13 + 5 =7 + 18-15 =16-7-4=11-10 + 19=20-8 + 4=8 + 19-19=2 + 14-16=18 + 2 - 19=14-3-8=13-9 + 10=14-6 + 4=20 -12 + 7

12、=3+1+2=3-2+5二9-3 + 14=14 + 4-8=11 + 11-2 =11 + 18-15 =19 - 18 - 1 =18 - 16 + 12 =10 -6 + 16=1 + 10 + 3 =I + 15 + 1=II + 2 + 6=13 + 9-19=18-1- 12 =2 + 12 - 11=9-7-1二19 + 14-20二13 + 17-13 =8+6+6=3+5+5=2 + 14-1 =5 + 15 - 20=16-12 + 2 =8+8+1=16-13 + 13 =8 + 3 - 3二17-3-4=12-1-9=20-17 + 12 =19 + 11 - 10=6

13、 + 12 - 14=12 + 7-10=11 -8 + 1 =5+6+5=6 + 7 + 1=14 + 3 - 17=13-7-2 =13 + 8-20=5 + 13-6=1 + 19-1 =19-12 + 1 =18 - 11 + 10=19 + 12-20=15 - 14 + 17=3+6+5=10-8 + 12 =17-11 + 9=20-8 + 5 =18-7 + 2 =13-4 + 9=10 + 14-5 =17 - 13 - 1=12-6 + 4=12 + 8-5 =16 - 16 + 5 =16-10 + 5=6-1+3二19-6 + 1=10-5 + 1=16 - 13 +

14、10=17-3-6=2+6+7=3+7-8二20 - 18 + 16=10 + 2 + 8=7-7 + 10=8 + 5-12 =16-5 + 5 =18-15 + 5=10 + 8 - 12 =12 -10 + 13 =13 + 12 - 16=17 - 5 - 10=14 + 3 + 2 =1+6+4=20 -19 + 6=8-2-1=14-8 + 12 =10 + 16-17=7-2+3二7+1+8=11 + 16-19=11 + 2 - 10=1+5+6=8+8+4=18 -13 + 8=2-2+9二18 + 17-16=17 + 4-3 =15-7 + 5 =19 + 13 - 14

15、=16 + 15 - 12 =3 + 1 + 11 =12 -10 + 7= 13-4-7= 18-4-8=3-3 + 17=11 -8 + 9= 8-5 + 14=10-2-6=5 + 15-4=11-9 + 1=13-4-3 =19-6 + 2 =9-3+6二3 + 1 + 10=15 - 5 + 3二17-5-3 =18-5 + 7=20 - 13 - 1=11 + 1 + 5 =4+8-4=17-14 + 4=9+3+3=19 + 1-6=14 + 3 + 3 =16 -14 + 7=15-6-1=15 - 12 + 13 =20-1-6=16 + 16-20=18-8-9=19 -

16、14 + 14=11 + 5 - 16=19 + 12 - 11=17 + 5 - 15 =2 + 10-5 =1+2+2=19 - 14 + 11=5 + 18-13 =11-2 + 8=17 -12 + 8=19 - 13 - 5 =15-3-9=10-7-3 =9 + 10-13 =15 + 19-18=4-2 + 18=19-4 + 5 二9 + 16-14=12 - 12 + 4=6-2 + 13 =17 + 6-6=9 + 11-3 =7+1+9=20 - 12 - 7=14 + 3 + 1=19 + 1-1 =15-2 + 2二8-3-1=19 + 12 - 17=2+7+2=6

17、-3 + 13 =6+1-1=11 + 13-20=16-6 + 9=11 + 6-6=1 + 15-4=13-7 + 11=16 - 15 + 19=20 + 16-18=14-11 + 12 =18 -15 + 1=11 + 4-6=2+4+8=7-2+9=8 + 12-5 =19 + 1-2=8-1+4=6-2 + 15 =16 + 11 - 14=5 + 3 + 1=2 + 15 - 11=15-9 + 9二2-1+6=5 + 10 + 4=13-2 + 4二13 + 20- 20=9 + 12-9=14-13 + 6=16-9-1二16 + 1-1=3+8+3=17 - 3 - 10

18、=11-2 + 11=3+7+8=12 + 13 - 5=6 + 15 - 15=7+7+4=14 + 3-2 =2 + 11-9=16 + 20-16=15 - 11 + 1 =19-7-1=9-4 + 12 =2 + 4 + 14=10-10 + 8=10 + 6-6=2+6-1=8+9+1=15 + 4-9二3 + 17-11 =9 + 7-11 =11 + 3 + 4=3 + 10 + 4=20-8 + 7=1 + 5 + 12 =10-8 + 1 =10 + 5-2 =11 + 6-2 =7-7 + 14=10-1-4=6-3-3=14-6-4=2 + 5 + 12 =8-8+4=1

19、2 -12 + 1=14-6 + 8=18-6-9=8-4-2=1 + 10 + 7=5+9-4二17-8 + 7=14 + 3-1=2 + 13 + 3=18 + 10-10=13-3-4=10 + 10-18=12-1-4=14-1 + 7=18 + 5- 15=12 + 3-3 =8 -4 + 1二9+5-1=1+9-6二18 - 10 - 3二7 + 10-8=20 - 17 - 3二8 + 16-17=9-9 + 19=5+4+6=15-9-2 =17-8 + 9=17 - 15 + 4=19-3- 10=13-4 + 4=19-18 + 6=2+9+2=13 + 12 - 14=3

20、 + 16-2 =15 + 10-14= 10-9 + 19=19 - 14 - 1二14 + 13 -18=19-14 + 4=7+2+9=20-13 + 12=17-8-2 =19 - 17 - 1=1 + 3 + 13 =2 + 12 + 5 =3-2+1二11-6-4=11 + 17-16=13 + 2 + 2=17-2-9=8 - 5 + 11二12 + 5-6=19 + 13 -12=20-12-2 =3 + 13-13 =6+5+7=15-7 + 9=15 - 15 + 7=19 + 7-18=4+5+6=14-5 + 7=19 - 17 + 11=9 + 12 - 15=4-3

21、+8二6 + 20-18=16 + 19 -18=错误率：9-9+9=3+1+3=15 + 4-19=6 + 4-10 二18-1-3=3-1+9=18 -14 + 14=20 + 2 -15=6-5 + 14=12-1 + 1=11 + 8 - 1=1 + 19 - 12=3+9-8二17 + 6-16=1 + 8 + 11=7-1+3=2-2+5二7-5 + 13 =5 -1 + 13 =6+3+5=17-9-2 =17-4-12 =4 + 19-16=5-4 + 14=1+9-7=19-2- 16=17-13-3 =7 + 11-4=18 + 12 - 10=13 + 13 - 12 =

22、8 + 13 - 14=20 -11 - 7=20-18 + 2 =1 + 1 + 11 =4+9+6=15-9-5 =16-2- 10=6 + 15-10=15 + 3 + 1=15 -2 + 3二10-5-3 =20 + 6-18=17 - 17 + 18=16 + 2 + 2=5+8-2二11 + 9 - 14=1+2+1=10 + 5 - 14=18-11-4=17 + 3-8=4+7+2=8 + 17-14=19 + 3-19=7 + 17-11 =16 + 2 - 17=20-12- 3 =16-14 + 8=9 + 19-20二6 + 11-9=12-7 + 13 =20-9-9

23、=9+1-9二16-3-9=15 -11-4=16 - 12 + 11=18-10 + 7=14-10 + 8=7 + 14-11=6 + 18-13 =2 + 15-2 =18-1 + 2=5 + 20-5 =4+1+5=18-2 + 3 =19-13 + 5=2+6+9=4+6+3=18-6 - 12=4 + 19-19=4+2+4=10 + 19-9=15-2-12=8+5-2=10-9 + 16=15 - 13 + 17=13-4 + 7=9-1 + 12 =2 + 3 + 14=4+9+1=4+5+4=4-2+9二1 + 2 + 16=15 + 10-7=19-6 + 5二19 -

24、1 - 11=2 + 12 + 3 = 15-4-11=17 - 1 - 16=4 + 6-10= 13-7-3 =1+5-2二3 + 14-7= 11-8 + 13 =13-9 + 5 =14-1-4=15-8 + 5 =17-8 + 11=15 + 4-5 二1 + 13 + 4 =14-2 + 6=13 + 8-19=7-1+9=6 + 14-7=5-4+2=17-16 + 5 =3 + 12-1 二9-3 + 12 =2+6-2二16 + 11-11=18 - 12 + 11=4 + 13 + 2=16 + 2 - 13 =16-6 + 7=17-4 + 5=5-5 + 19=3 +

25、13-7=5+4+7=12 - 11 + 2 =17-6-5 =12 - 10+ 10 二12 -11 + 16=3 + 16-3 =17 + 5-8=3 + 17-13 =20-9-7=1+5+2=14-6 + 11=17-9 + 8=13 - 13 + 10=6 + 19-7=19-6-8=4+4+7=4+1-4=15 + 5-1=3+1+7=8 + 19-13 =13 + 16-18=16-5 + 9=19 - 11 + 4=6 + 12 - 12=18-1- 16=18 -4 + 4二5+5-9=19 - 5 - 12 =19 + 4-10=2 + 2 + 13=7-5+8=6+2-6

26、=19-10-3 =20 + 1 - 18=14-9 + 14=11 + 8-6=15 + 10-12=4-2 + 15 =7-1-6=8-3 + 14=3+7+3=12 - 11 + 3 =12 + 7-12 =1+5+1=7 + 11-16=17-1-3 =11-8 + 6=5 + 7-12=7 + 19-9=11 + 1 - 5二13 - 11 + 14=17 + 3 - 18=19 -3 + 4=7 + 12-3 =13-6 + 3二10 + 17-8=19-14 + 3 =11-9 + 7=11-6 + 12 =2+2+4=11 + 11 - 12 =15 - 1 + 1 =2+1+

27、3=19-6-12 =15 + 3 - 13 =20-3-8=17 + 5-9=2+6+4=14 + 2-6=15 - 12 + 14=5-3 + 14=13 + 2-2 =10-7 + 7=18 - 11 + 4=3+8+5=7 + 5-11=17-6-1=15 + 18-18=1 + 3 + 15 =6-4+7二13 + 5 - 11=17 - 11 + 14=4+6+7=5-3+1=12 + 2-2 =15 + 6-14=14-6 + 10=5 + 8 + 1=5-4 + 11=4+9-7二20 - 20 + 13 =19 - 14 - 4=2 + 19-18=2 + 15-4=7+3+

28、2=9+8-9二18 + 15 - 17=15 - 14 + 19=15 + 13 - 10=11 -3 + 9=15 + 5 - 11=11 - 11 + 2 =4 + 10-11=10-5 + 12 =16 + 1-4=9 -4 + 15二2 + 12-5 =17-8 + 4=14- 5 + 4二11 -3 + 10=14-8-3 =13 + 1-9=6+8-1二20-4-16=13 + 11-20=17 + 4-13 =18-3-13 =16 + 20 - 20=12 + 4-2二20-7 + 6=9 + 10-4=8-1-2=17 + 10-13 =9-8+6=18 + 15 - 16

29、=20-1- 18=18 - 10 - 6=13 + 3-5 =4 + 20-13 =6+9-9二20-15 + 8=14-7 + 5 =5+5-8=17 - 10 + 12=11-1-6=7-2-3=3+ 14 + 1=19 - 15 + 5 =3 + 11-10=5-1 + 14=15 - 5 + 1 =14-2-3 =1+4-5=6+6-4=14-13 + 2 =6-2+3=9-7+2二6-1-1=3 + 17-5 =10-5 + 5 =14-13 + 11 =10 - 10 + 15 =18-3-15 =5-1-2=14 + 1 + 2 =2-2+2=10-1 + 1=13 + 2 -

30、 1=7-3-2=18 - 15 + 10=8 + 16-16=7-3 + 16=15 + 15 - 13 =14 - 10 - 4二19-13 + 9=9 + 3 - 5二2+4+3=10-4 + 3 =12-6 + 8=19-19 + 7=7+4+5=10-4 + 6=1 + 18-13 =3+9+2=9 + 17-14=10 + 20-19=13 + 16-17=13 -8 + 3 =19-2 + 1=9 + 19-17=16-6 + 2 =20-14 + 5 =20 -6 + 3 =8+3+9=8 + 4- 5二8 + 18 - 15=8+1-5二14-10-2 =18 - 14 -

31、1=4-1 + 12 =13 - 1 - 11=18-9 + 5=20-13 + 5 =20-3- 10=13 + 2 -15=19 - 10 - 2 =19 -19 + 6=11 -1 + 7=18 + 2 - 13 =10-5 + 4二15-9 + 7二4+4-8二15 - 5 + 2二10-7 + 2 =15-4-6=12-3 + 3 =12-5 + 6=17 -17 + 7=19 - 10 - 9二6-1 + 10=7 + 12 + 1=7 + 12 - 11=11 + 15 - 11=2+9-3二10-4-4=15 + 10-15=6 + 14-1 =4 + 13-7=10-9 +

32、14=10-5 + 10=16-1-3 =19-18 + 1=17-1 + 3 =20-17 + 2 =13 + 16-16=10-2 + 1 =7+7-9二2 + 20-5 =17-10 + 13 =9+1+1=15 + 13 -13 =7+4+2=4 + 7-11 =16-14 + 14=4 + 17-2 =16-2 + 1=18 - 11 + 13 =8-1+7=19-6-2 =14-7 + 2 =7-4 + 10=10 + 2-7=14 + 4-6二13-8 + 8=5 + 19-7=14-3 + 8=1 + 11 + 4=17 -14 + 9=5+9+4=14 + 6- 16二10

33、+ 8-15 =6 - 4 + 4=13-9 + 3二17 - 16 + 7=5 - 5 + 2 =4+5-8=15 - 14 + 1=2 + 3 + 15 =16-8-8=19 - 1 - 10=14-10 + 11=9+4+1=3+4+8=13 + 17-19=16 + 6-15 =16-14 + 12=5+2-3=18 -15 + 15=10-8 + 2 =4 + 20-16=20 + 14-18=10 + 10-19=19 -16 - 2=11 -3 + 6=8 + 14-19=13 + 4-12 =10 + 8-7=6-4 + 16二3-3+1=5+5+1=13 + 13-20=11

34、-9 + 13 =18 -16 - 2=10-9 + 4=3 + 18-14=11 + 2-8=15-1- 14=11-10 + 6=15-4-4=12 + 12-9=8 - 5 + 5二18 + 18-17=19 -18 + 2 =3+1+8=20-8-7=3+6+8=9 + 13-8=2+1+2=19 + 16-20=17 -14 + 6=16-2- 12 =11 + 12 - 11=5-4+4=12 - 12 + 12 =9 + 11-1 =15 + 7-7=5+5-1=7+5-8二19 + 8-7=13 + 7-19=4 + 11 + 5 =15 -6 + 6=1-1+3=14-14

35、+ 16=5 + 16-11=9-9 + 10=8-1+9=8-7 + 10=7 + 13-20二12-8-2 =17 - 12 + 11=1 + 5 + 10=9-3+7=12-9 + 15=13-1-2 =2+6+5=4 + 17-9二2 + 10 + 2=7+3+4=11 + 8-18=10-2 + 3 =4-1 + 14=13-1 + 8=11 -3 + 7=16 + 13 - 11=16-7 + 4=15 + 3 - 12 =15 - 12 + 1 =5+7+4=16-4 + 2二1+3+1=17 + 3 - 13 =14-11 + 3 =14-5 + 9=6+2+4=12-7 +

36、11=4-4 + 14=10-8 + 14=4-4 + 20=4 + 4- 5二19 + 14-17=17-1-6=19 -17 + 8=8-4-4=18 + 8-16=15-5-2 =15 + 11 - 10=12 + 19-15=8+4+6=7 + 19-17=1 + 16-13 =17 + 14-17=16-2-8=16 + 9-6=15 + 9-4二6-2 + 10=16-4 + 7=16-4-1=8-2+8二5-3 + 13二16-11 + 8=8 + 16-7=14-5-2 =15 + 10-17=12-9 + 10=16-5 + 3二10-9 + 6=15 -13 + 13=13

37、-1 + 5=9 + 11-11=19-1-7=20 + 5-5=1 + 3 + 11 =15 -1 + 4=12 - 11 + 11=18-18 + 20=12 + 10-19=19-15 + 11=18-18 + 11=8+2-7二7+8+5=10 + 14-20=1 + 2 - 3二2 + 19-17=3 + 10-12 =13-6 + 5=7-5 + 14=18 + 11-14=15 + 16-18=3 + 18-2 =2+5+9=15 - 15 + 9=16 + 12 - 18=2 + 18-8=6-2+7二6+9-1=14 + 2 - 12 =7-6 + 11=17 + 13-20

38、=2 -1 + 15 =14-14 + 14=17-1-9=2+4+9=19-4-9=10-8 + 9=2-2 + 10=19 - 15 + 14=20-2-12 =8-5 + 16=14-6 + 2 =6 + 6-12=4 + 18-12 =18 - 1 - 11 =6-2 + 16=19-16-3 =6+2+9=18 -18 + 8=13 + 1 + 3=9+6+3=17 - 11 + 1=6+6-3=18 + 1 - 13 =16-14 + 15 =12 - 10 + 16=9 + 11 - 12 =4 + 19-8=7-5-1=17-9-7=1 + 16-15 =17-16 + 17=

39、7-4-3=8+3+8=20-19 + 14=1+9-2=19-8-8=8-6 + 13二20-4-5=14 + 15 - 13 =9 + 19-12 =4 + 13-6=2-1+4=16 + 11 - 10=9 + 17-16=5+1+2=6 + 11-12 =8-5 + 13 =18-1-13 =18-5-13 =19-9-9=4 + 13 - 14=9-7 + 12 =11 + 10-4=16-5-4=14-11-3 =7 + 14-16=2 + 18-14=7-7 + 11=6 + 12 - 18=13 + 6-13 =6-6 + 17=10-3 + 6=16-12 + 15 =8-7

40、+9二18-2- 10=12 + 8-6=9-7+1二19 + 9-13 =14-4 + 8=15-1-7=5-1-4=2-1 + 17=17 - 10 - 4=6 + 14-9=1 + 11 - 12 =3 + 12 - 11=18 - 16 + 3 =18 + 7-12 =1 + 11 + 5 =2+4-3二15 - 12+ 5=20-6 - 10=18-3 + 5 =3 + 15 + 1=10-6-3 =20-15 + 7=12 - 11 + 10=14-12 + 7=13-3 + 8=16 + 8-7=6-2+9=20-16 + 1=8 + 9-11 =11 + 19-20=11 +

41、6 + 2 =5 + 13 + 1=10 + 9-14=12-5-4=18 + 15 - 18=5 + 12 - 15 =16 + 18-19=11 + 12-20=5 + 13-13 =13 - 12 + 19=10-3 + 7=10-2-3 =14 + 17-19=14 + 6-3 =20-5-1=13 + 13 - 18=8+9-2二6+1+7=6 + 20-9=20 + 8-9=17 - 17 + 12 =10 + 3 + 3 =18 - 13 - 2=3 + 3 + 11 =2+7-5=17 - 16 + 15=16-4 + 6二20 + 14 - 14=1 + 14 + 3 =19-3-4=13 - 10 + 17=3-3+7=8 + 17-13 =2-2 + 12 =16-1-1=14 + 10-13 =15 + 5-6=15 -12 + 16=6+5-7=13-9-4=20-12 + 11 =13-6 + 6=1