какие числа делятся и на 3 и на 4?

Все числа, кратные 12 = (3 * 4).    Например: 24 : 3 = 8;  24 : 4 = 6

                                                                    36 : 3 = 12;  36 : 4 = 9

                                                                    48 : 3 = 16;   48 : 4 = 12

                                                                    60 : 3 = 20;  60 : 4 = 15

                                                                    и т.д.