20以内三连减口算练习题(80).docx

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

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

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

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

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

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

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

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

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

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

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

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

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

14、1 =18-1-9=19-5- 10=17-2-13 =20-2-11 =13-9-2 =20-9- 10=20-3-11 =15-6-8=16-3-8=11-2-9=15 - 1 - 11 =7-4-2=16 -10 - 3=19-6-12 =18-4-7=9-1-6=17-3-2 =19-14-2 =19-1-1=20-1- 12 =18-15-2 =19 - 13 - 6=15 - 13 - 1=16-6-1=19-1-11=14-5-2 =12-4-2 =16-2- 10=20-5-3 =19-2- 14=17-3-6=20-11-3 =18-2-2 =14-2-12 =错误率,PH2

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

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

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

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

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

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

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

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

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

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

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

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

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

28、0-1-7=15-5-6=15-4-4=12-8-3 =20-1-1=20-5-4=18-3-6=17-3- 12 =15 - 11 - 1=19-3- 12=16-9-2 =20-6-6=19-1-8=18 - 1 - 17=18-1-3 =16-1-6=20-4- 14=16-8-6=11-3-1 =17-4-7=16-2-9=13-9-4=12-2-4=11-7-4=14-9-4=13-2-9=13-7-4=20-4-5 =15 -14 - 1=10-4-1=10-1-8=13-2-11=15 - 3 - 12=12-3-2=17-2-7=19-8-5 =10-1-9=20 - 5 -

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

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

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

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

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

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

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

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

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

38、9=13-4-3 =15-4-10=12-1-11=18-7-8=18-7-4=错误率,PH11-10-1 =17-4-11 =12-1-8=20 - 12 - 4=10-1-5 =19-3- 16=13-1-6=14-3-3 =20 - 10 - 8=11-1-8=18-2-1=19 - 10 - 9二12-5-1=20-4-2 =19 - 11 - 6=13-5-3 =15-2-9=17-5- 10=8-1-6=20-8-6=20-7-13 =18-5-4=19-8-1 =20-8-5 =13-5-1 =18-11-2=17-1-11 =11-1-5 =15-8-4=20-3-3 =19-

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

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