20-9= 11-9= 13-7=

4+11= 1+18= 19-18=

7+13= 1+7= 13+2=

17-8= 17-7= 2+5=

3-2= 7+10= 16-10=

5+6= 11-10= 18-16=

14-2= 18-2= 11+7=

7+12= 9-1= 10-8=

20-15= 10-9= 20-8=

20-11= 20-5= 20-18=

14+2= 14-10= 6+11=

12+7= 12-10= 14+5=

18-4= 9+8= 6+3=

16-4= 18-12= 1+17=

14+2= 4+4= 10-2=

14-6= 12-6= 12+6=

11-3= 15+2= 5+13=

9+6= 2+1= 16-14=

1+8= 4+12= 3+13=

14-3= 18-5= 7+6=

12+1= 12-1= 19-15=

18-1= 13-11= 16+1=

9-2= 16-7= 16-15=

18-14= 18-5= 16+4=

20-16= 17-5= 20-19=

10-5= 11-4= 1+8=

16-11= 17-5= 6+2=

6+10= 14-9= 18-11=

2+13= 6+8= 13-12=

13-3= 8+5= 19-4=

19-18= 7-4= 6+13=

17-3= 1+17= 20-6=

7-2= 5-2= 7+3=

14-2= 15+4= 14-8=

17-6= 11-2= 20-15=

6+2= 11-8= 9-4=

16-6= 14+1= 2+5=

2+17= 2+10= 8+12=

14+3= 8-2= 17+1=

20-5= 18-13= 11-9=

18-15= 15-9= 1+8=

19-14= 10+5= 19-12=

20-13= 12-9= 18-6=

14-8= 7+8= 18-14=

11-8= 8-7= 17+3=

1+3= 7-4= 2+5=

5-2= 14-3= 8+9=

13-1= 9+3= 7+12=

17-3= 20-19= 5-1=

20-15= 19-18= 12+2=

15-5= 12-3= 6+4=

7+5= 19-8= 18-11=

19-13= 8+9= 10-4=

2+3= 3+1= 4+10=

7+6= 8+9= 3+15=

12-3= 1+18= 19-12=

15-1= 11+2= 7+4=

15-5= 9-3= 19-9=

17+2= 6+12= 10+1=

9+7= 11-5= 15-1=

1+5= 14+5= 2+11=

4+4= 6-1= 4+15=

2+10= 17-3= 15+2=