1)
dam factor comun convenabil pt a pune in evidenta suma lui Gauss pe care stim sa o calculam cu formula cunoscuta
2(1+2+....100)=2*100*101/2=100*101=10100
2) 3 (1+2+...+100)=3*100*101/2=3*50*101=15150
3) la fel vom avea 6*100*101/2=30300
4)...8*100*101/2=40400
5)...7*100*101/2=35350