1)
(4 5/6 - 2,5) * 12 - 27 * 5/9 = 13,
1) 4 5/6 - 2,5 = 29/6 - 25/10 = 145/30 - 75/30 = 70/30 = 7/3 = 2 1/3,
2) 2 1/3 * 12 = 7/3 * 12 = 7 * 4 = 28,
3) 27 * 5/9 = 3 * 5 = 15,
4) 28 - 15 = 13,
2)
(2 7/12 + 1,75) : 13 + 2,5 : 3 3/4 = 1,
1) 2 7/12 + 1,75 = 31/12 + 175/100 = 775/300 + 525/300 = 1300/300 = 4 1/3
2) 4 1/3 : 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