(3/4 - 5/6) ×3+(3/4+5/6) ×4

Решение по действиям:
1) 3/4 - 5/6 = 9/12 - 10/12 = - 1/12
2) - 1/12 * 3 = - 3/12 = - 1/4
3) 3/4 + 5/6 = 9/12 + 10/12 = 19/12
4) 19/12 * 4 = 19/3
5) - 1/4 + 19/3 = - 3/12 + 76/12 = 73/12 = 6целых  1/12