a.1+3+5+7+9+....+99 b.1-2+3-4+5-6+7-8+....-100 c.-100-99-98-...-2-1-0+1+2+...+48+ 49+50 tolong dijawab buat besok

1+3+5+7+9.....+99
= 1+99= 100
=3+9=12
=5+7=12
= 100: 2= 50
= 50x12= 600
b. 1-(-100)=99
= 2+8= 10
= 3+7=10
= 4+6=10
5=5
99:3=33
=33x5=165