1)4целых 11/48 помножить 6/7 минус 1 целая 4/9 пример 2) 15

1) 4 11/48 * 6/7 - 1 4/9 = (4 * 48 + 11)/48 * 6/7 - (1 * 9 + 4)/9 = (192 + 11)/48 * 6/7 - (9 + 4)/9 = 203/48 * 6/7 - 13/9 = (203 * 6)/(48 * 7) - 13/9 = 29/8 - 13/9 = 9 * 29/72 - 8 * 13/72 = (261 - 104)/72 = 157/72;

Ответ: 157/72.

2) 15 4/7 - 4 3/8 * (1 9/7 - 34/35) = (15 * 7 + 4)/7 - (4 * 8 + 3)/8 * (16/7 - 34/35) = (105 + 4)/7 - (32 + 3)/8 * (5 * 16/35 - 34/35) = 109/7 - 35/8 * (80/35 - 34/35) = 109/7 - 35/8 * (80 - 34)/35 = 109/7 - 35/8 * 46/35 = 109/7 - 23/4 = 4 * 109/28 - 7 * 23/28 = (436 - 161)/28 = 275/28;

Ответ: 275/28.