A) -37+54+(-70)+(-163)+246
= (-37-163)+(54+246)+(-70)
= -200 +300-70
=30
.
B) -359+181+(-123)+350+(-172)
= -178-123+350-172
=-301+350-172
=49-172
.
C) -69+53+46+(-94)+(-14)+78
=-16+46-94-14+78
=30-94-14+78
=-64-14+78
=-78+78=0
.
d); 13-12+11+10-9+8-7-6+5-4+3+2-1
=1+11+10-9+8-7-6+5-4+3+2-1
=12+10-9+8-7-6+5-4+3+2-1
=22-9+8-7-6+5-4+3+2-1
=13+8-7-6+5-4+3+2-1
=21-7-6+5-4+3+2-1
=14-6+5-4+3+2-1
=8+5-4+3+2-1
=13-4+3+2-1
=9+3+2-1
=12+2-1
=14-1
=13