20以内三连减口算练习题(161).docx

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

2、率,PH20 - 16 - 4=19 - 13 - 2 =18-7-3 =20 - 17 - 3二8-3-2=20-1-7=12-4-6=19-9-4=18-6-5=13-1-1=11 -1 - 10=18-3-6=19-16-3 =17-8-9=16-5-1=19-11-7=17-1-2 =7-2-1=16-5-8=11-2-2 =17-2-2 =17-8-6=20-6-7二14-1-12 =20-2-13 =9-1-1=9-7-1=19-5-4=20-9-2=20-2- 17=18-3- 14=8-4-2=20-8-9=14-7-2 =20 - 10 - 6=9-5-3=20-2-3 =1

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

4、-4=14-6-6=15-3-5=11-4-7=15-1-2 =19-6-5 =16-2-5=14-3-11 =20 -10 - 5=20-4-5=9-1-3=18-5-2 =17-9-3 =19 - 14 - 1 二18-1-9=19-5-7=15-2-11 =18-2-2 =17-5-8=18 - 12 - 5 =16-8-1=19-6-4=12-4-8=19 - 10 - 7=13-4-8=18-8-3 =18 - 13 - 2 =17 - 11 - 5二19-4-8=16-7-9=12-7-3 =15-3-6=7-5-1二错误率：13 - 12 - 1= 15-4-8=19 - 17

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

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

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

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

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

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

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

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

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

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

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

16、8=16-3-4=18-1- 12 =13-6-4=10-5-3 =15-2-9 =15-11-4=15-2-1=20-5-4=7-4-2=11-2-4=18 -13-4= 19-9-6=18 - 12 - 2=17-8-5 =13-2-7=19-2-3 =18-2-13 =17-7-5 =16-14-2 =错误率,PH19-11-5 =20-3-8=7-4-3=11-1-9=20-7-7=19-11-1=19-4-10=10-2-3 =19 - 12 - 4=19-8-9=14-5-7=16-5-11 =20 - 3 - 11=15-8-7二11-5-4=13-3-6=17 - 10 - 1

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

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

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

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

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

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

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

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

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

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

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

28、6-11=11-4-1=19-11-6=错误率,PH19-14-5 =20-10-2 =17-1-4=11-7-2 =12-7-2 =16-5-5 =14-2-1=17-5-9=17-8-3 =19-5-2 =20-2-6=15-1-3 =19-3-8=15 - 3 - 10=15-4-5=10-3-6=8-4-4=16-13-3 =18-2- 14=7-2-4=16-6-7=13-8-3=18-8-4=20-4-4=17-7-4=13-7-3 =19-16-2 =10-4-5 =20-2-7=20-3-15 =18-12-4=16-2-13 =10-6-4=19-7-9=20-11-9=19

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

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

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

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

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

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

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

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

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

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

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

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