Question

Calculati suma resturilor posibile ale impartirii unui numar natural la 9. Ajutor rapid!!!!!!!!!!!!! 

Answer 1

D : I=C, +R
R < I

R < I   =>R={0,1,2,3,4,5,6,7,8}

Suma resturilor= 0+1+2+...+8

S=(0+8)*9/2

S=4*9

S=36