Question

aflati cate numere de trei cifre dau restul 8 la impartirea cu 13

Answer 1

x : 8 = c  (rest 13)  ⇔  x=M₈ + 13

                                             ↓

                                   100 ≤ x ≤ 999

⇒ (100-13) : 8 ≈10,8...    si  (999-13) : 8 ≈ 123,2...

x={11*8+13=101; 12*8+13=109; 13*8+13=117; ... ;123*8+13=997}

                      Avem in total (997-11)+1 = 987 numere !