Răspuns :
15-5-5-5=0
16-4-4-4-4=0
18-3-3-3-3-3-3=0
27-3-3-3-3-3-3-3-3-3=0
45-9-9-9-9-9=0
49-7-7-7-7-7-7-7=0
16-4-4-4-4=0
18-3-3-3-3-3-3=0
27-3-3-3-3-3-3-3-3-3=0
45-9-9-9-9-9=0
49-7-7-7-7-7-7-7=0
15-5=10; 10-5=5; 5-5=0. 16-4=12 ;12-4=8;8-8=0. 18-3=15;15-3=12; 12-12=0 AI SI B