15-(5+2) = 15-7=8
(26-6)+20 = 20+20=40
17-10+5 =17-10=7+5+12
8+3-4 = 11-4 = 7
10+2-7= 12-7 = 5
7+6-0 = 13-0 = 13
15-(5+2)=15-7=8
(26-6)+20=20+20=40
17-10+5=7+5=12
8+3-4=11-4=7
10+2-7=12-7=5
7+6-0=12