11-3=11-4=11-5=
13-6=13-7=13-8=
15-9=15-8=15-7=
15-8= 8+=17 8+=16
8+=15
(答案不唯一)
12-3= 15-7= 16-8= 11-5=
9+5= 10+7= 15+4= 8+9=
13-8= 12-7= 14-8= 16-7=
12-45 15-78 13-48
12-64 718-9 413-3