20以内三连加减混合口算练习题(291).docx

《20以内三连加减混合口算练习题(291).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(291).docx（55页珍藏版）》请在淘文阁 - 分享文档赚钱的网站上搜索。

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

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

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

4、0-9=4 + 19-17=8+9+3=8-4-2=7+5-9二3-3+2二9 + 10 + 1=8-4 + 15 =6-6+8=16-6- 10=20 -19 + 18=5+8+4=2+2+2=15-1-1=15-6-8=15-3-4=4 + 1 + 12 =3-3 + 16 二9-6+7二5+3-6=14-13 + 17=1 + 20-8=18-10 + 3 =19-5-5 =7-7 + 11=3-1+7=5 + 18-9=15 - 3 + 2=13 + 5 + 2=8 + 18-13 =1+6-7二11-6-1 =9 + 6-13 =3 + 2 + 14=5 + 1 + 12 =3+4-

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

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

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

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

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

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

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

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

13、0=14 + 6-11 =1 + 2 - 3二20-16 + 12=9+7-5二9-2 + 10=13-3-9=5 + 12 - 17=17-14 + 4=1 + 15 - 16=15 + 1 + 2=6-2+4=11 + 10-7=3+6-3二15 -6 + 4=14 + 13 - 19=15 - 10 + 9=18-5-4=17-13 + 9=2 + 16-17=15-13-2 =18-4 + 5=18 - 16 + 4=10 + 9-12 =20 + 7-7=3 + 10-11=1 + 11-4=17 -10 + 9=10-3 + 8=18 + 7-15 =19 - 1 - 18=19-

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

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

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

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

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

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

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

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

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

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

24、 =10-5 + 9=8-8 + 14=5 + 11 - 12 =20 + 4-12=10 + 17-16=14-5 + 3 =7 -4 + 17二8 -4 + 2二5 + 11 + 2=8 + 5 - 12=13 -8 + 4=5+3+4=14 + 3-8=1 + 6 + 12 = 20-1-11= 19 -18 + 9=17 + 7-5 =1 + 9-10=10-2 + 12 =3-1 + 10=9-2+1二14 + 3 - 16=4+8+1=14 + 10-19=15 + 16-19=7 + 16-11=3-2+1二6+4-5二19-4- 10=12-6-5 =20-13 + 3 =12

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

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

27、 =7-7 + 20=18 - 12 - 1=19-15 + 4=20-4-12=9-8 + 17=14 + 2-1 =10-4 + 14=19-2-11=11-5-2=3+4+3=7+5-3=10-4-4=14-12 + 12=8+7-9=9 + 17-20=13 + 1-3 =16-13+ 3二17 + 16-14=13 + 1-13 =6+8+2=15 + 9-11 =4-4 + 15二4-4+7二14 + 16-20=16 -11 + 5 =12 + 8-7=17 + 20-19=13 + 20-18=4-2+4二12 + 8-19=17 + 8-19=15 - 11 + 14=16

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

29、 + 12-6=8+8-6二2-2 + 18=12-7 + 2 =2 + 1 + 13 =4 + 18-9=4+2-2二13 + 7 - 10=15-7-5 =15 - 15 + 2=5+7+5=20-19 + 3 =17-3 + 1=19 - 14 + 8 二11 + 13 - 5 二6+3-4=6 + 16-16=15 + 5-15 =18 + 10-20=7+5+8=15-1-9=13 + 16-11=1 + 12 - 13 =9-5 + 14=14 + 5-1=11 + 18-20=12 - 12 + 20=16 + 4-20=5 + 20-18=18-11-7=15 + 8-12 =

30、12 + 12 - 14=10 + 20-17=3+7-3=12 - 12 + 14=10-9 + 1=20-13-2=14 + 7-18=8-7+3二16 + 2-1 =17 + 5-8=6 -5 + 15 =20 + 2 - 19=13-7 + 14=13 + 8-10=18-16 + 3 =9-4+6=12 + 4 + 3 =15 -15 + 3 =4-4+1二16-5-5 =12-1 + 3 =13-3-3 =14 + 12 - 12 =6+5+5=19-8 + 1 =20-17-3 =9 + 10-7=17-8 + 6=17-15 + 7=15 - 15 + 11=5-3+8=3 +

31、 12 + 4=7-7 + 19=17-8 + 10=10-8 + 2 =17-14 + 13 =3-1+8=4 + 19-8=10 + 16-17=13-6 + 6二16 + 2 - 12=16-4 + 7=20 -12 + 2 =17-9 + 9=4 + 10-7=15 + 10-20=15 + 13-9=2 + 16-10=11 - 11 + 19=20-18 + 9=13 - 11 + 7=11-9 + 6=8+2+9=18 - 13 - 5 =19-3-16=9-1+2=12 + 9-11 =17 + 7-18=16-3 + 5 =9+8-1=6 + 13-10=13 - 10 +

32、13 =16-10 + 4=20-9-3 =19 + 5-9=9-6-2=10 + 2 + 5 =10 + 17-11 =16-9-5 =6 + 10-5 =18 + 5 - 11 =14-13 + 4=1+9+4=10 + 3 + 4=6 + 18-12 =5+7+6=20-3-6=15-9 + 13 =3-2 + 16=1+5-5=17-5-6=13 - 12 + 12 =9-5+2=14-2 + 7=1+9+3=11-3 + 9=20-3-5 =5 + 13 + 2=2 + 14-11=7 + 19-13 =17-17 + 7=3+7+1=3+1+9=2+7-6二16-8 + 5 =13

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

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

35、0 -14 + 7=19 -4 + 3=5 + 14- 1二15-8 + 13 =10 + 14-18=1-1 + 12 =18 + 4-20=6 -4 + 5=17 -5 + 4=6 + 17-18=12-2-7=2+5+4=19 - 13 - 6二15-7 + 9=19-3-6=19-13 + 4=6 + 15 - 19=1+4+6=17-1-3 =4 + 13 + 2=11 -3 + 5 =20-1- 18=7 + 15-20=10-9 + 3 =8+9-5=19-9 - 10=12 + 19-11 =20 + 15 -20=2 + 2 +16=18-15-3 =18-9-9=16-13

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

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

38、- 11 + 2 =8-5 + 14=8-7 + 10=18 + 1- 14=18 + 1 - 1 =9+4+6=20 - 11 + 2 =16-12 + 15 =9-9 + 20=7-1+6=17 + 7-15 =19-2-4=20-3- 17=11 + 18 - 12=20 - 10 - 9=14-9-2 =8-3+5=15 - 15 + 18=7+8+2=19 + 15-20=12 + 6 + 1=16 + 6-13 =2 + 15-8=10-4 + 8=3+5+3=18 + 17-18=15 - 8 + 6二13 - 13 + 2=11 + 17-14=18 -17 + 7=3 + 1

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

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

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