47
Пошаговое объяснение:
1) 2,75 + 1 1/6 = 275/100 (3) + 7/6 (50) = 1175/300 = 47/12 = 1 11/12
2) 2 1/3 * 3 1/7 = 7/3 * 22/7 = 22/3 = 7 1/3
3) 7 1/3 - 7 1/4 = 22/3 (4) - 23/4 (3) = 1/12
4) 3 11/12 : 1/12 = 47/12 : 1/12 = 47/12 * 12/1 = 47
