Ответ:
3 1/19
9
Пошаговое объяснение:
№ 2
(4 1/5 - 2 3/4) * 2 2/19 = (4 4/20 - 2 15/20) * 40/19 = (3 24/20 - 2 15/20) * 40/19 = 1 9/20 * 40/19 = 29/20 * 40/19 = 29/1 * 2/19 = 58/19 = 3 1/19
№ 4
(7 5/12 - 3 1/6) * 2 2/17 = (7 5/12 - 3 2/12) * 36/17 = 4 3/12 * 36/17 =4 1/4 * 36/17 = 17/4 * 36/17 = 9