Răspuns:
[tex]a)35 \times 99 = 35 \times (100 - 1) = 3500 - 35 = 3465 \\ b)27 \times 101 = 27 \times (100 + 1) = 2700 + 27 = 2727 \\ c)15 \times 102 = 15 \times (100 + 2) = 1500 + 30 = 1530 \\ d)31 \times 98 = 31 \times (100 - 2) = 3100 - 62 = 3038 \\ e)999 \times 4 = 4 \times (1000 - 1) = 4000 - 4 = 3996 \\ f)1004 \times 5 = 5 \times (1000 + 4) = 5000 + 20 = 5020[/tex]