62
21
(-18-23+20)/3= (-21)/3=-7
18+18+18+19+23+23+24+24=167
18 + 23 + 23 = 64
23 + 21 = 44
No, 21- (5 plus 2) does NOT equal 23.
Commutativity or Abelian property
-21
-23
16 + 16 + 16 + 17 + 18 + 18 + 18 + 19 + 19 + 20 + 20 + 20 + 21 = 238
12 + 23 + 45 + 67 + 16 + 18 + 45 = 226
C+ (-2)= 21= 21+2= 23+ (-2)= 21 23+ (-2)= 21 is the same as 23- 2= 21