Răspuns :
Suma Gauss =a+b+c+..n=(n+a)*[(n-a):(b-a)+1]:2
75+80+85+90+95+100....555=(555+75)*[(555-75):5+1]:2=630*97:2=30555
75+80+85+90+95+100....555=(555+75)*[(555-75):5+1]:2=630*97:2=30555