文档介绍：(一)
13-7= 16-7= 12-7= 15-9= 9+5=
16-8= 11-5= 13-5= 13-6= 14-9=
11-2= 13-6= 12-4= 12-7= 14-5=
14-7= 15-8= 15-7= 6+8= 7+8=
12-3= 12-4= 13-4= 14-6= 15-7=
13-2-3= 7+12-9= 11+2-9= 15-1-9= 8+5+2=
11+3-5= 17-3-4= 18-7-9= 17-3-7= 12-2-1=
12-2-2= 13-2-6= 15―4―5= 13-5-3= 14-7-4=
17-5-3= 13-2-1= 17-5-5= 14-4-2= 13-3+2=
12+6-8= 10-9+3= 10-7+2= 10-8+4= 17-4-7=
12-8= 14-9= 9+6= 13-6= 7+7=
11-4= 18-9= 15-8= 16-3= 11-5=
14-9= 12-3= 15-6= 12-7= 3+8=
20-5= 9+9= 17-9= 11-8= 15-7=
11-9= 13-4= 9+5= 17-9= 17-8=
11-( )=6 12-( )=8 13-( )=6 14-( )=8 15-( )=9
( )-9=2 ( )-7=5 ( )-7=8 ( )-8=3 ( )-7=6
7+( )=12 9+( )=16 ( )+9=16 7+( )=15 ( )+9=12
16-( )=9 17-( )=9 13-( )=9 11-( )=7 13-( )=9
10-( )=3 14-( )=9 16-( )=8 15-( )=9 12-( )=6
(二)
13-8= 13-5= 16-9= 15-7= 13-7=
15-6= 11-3= 12-7= 13-4= 14-9=
17-9= 12-6= 13-6= 15-9= 12-5=
11-7= 17-8= 14-6= 16-8= 16-7=
12-3= 13-9= 15-8= 13-6= 16-8=
8+5+2= 7+5+3= 16-3-9= 14-7-4= 16―3―3=
12-2-1= 17-3-7= 14-4-1= 15-5-2= 11-1-1=
14-7-4= 13-5-3= 13―4―6= 17-5-5= 16-3-4=
13-3+2= 6+7+4= 10-9+4= 15-1-9= 10-9+1=
17-4-7= 9+3+1= 15-2-8= 17-5-2= 7+5+3=
11-7= 11-5= 11-7= 13-4= 15-2=
12-4= 12-6= 12-8= 13-9= 17-9=
13-9= 13-9= 13-6= 13-6= 13-4=
14-3= 14-7= 14-7= 13-8= 12-5=
15-9= 15-6= 15-8= 13-5= 15-6=
( )+9=13 9+( )=14 ( )+6=15 7+( )=14 7+( )=16
13-9=( ) 13-5=( ) 14-6=( ) ( )-8=6 ( )-7=6
9+( )=16 ( )+6=12 ( )+7=16 6+( )=15 ( )+5=12
11-6=( )