(4 5/6 - 2,5) * 12 - 27 * 5/9 = 43
1) 4 5/6 - 2,5 = 29/6 - 25/10 = (5*29 - 3*25)/30 = (145 - 75)/30 = 70/30= 7/3
2) 7/3 * 12 = 28
3) 27 * 5/9 = 15
4) 28 + 15 = 43
(2 7/12 + 1,75) : 13 + 2,5 : 3 3/4= 1
1) 2 7/12 + 1,75 = 31/12 + 175/100 = 31/12 + 7/4 = (31+21)/12 = 52/12= 13/3
2) 13/3 : 13 = 13/3 * 1/13 = 1/3
3) 2,5 : 3 3/4 = 25/10 : 15/4 = 25/10 * 4/15 = 2/3
4) 1/3 + 2/3 = 3/3 = 1