1) 13 3/4 + 9 1/6 = 13 9/12 + 9 2/12 = 22 11/12
2) 22 11/12 * 1 1/5 = 275/12 * 6/5 = 55/2 = 27,5
3) 10,3 - 8,5 = 1,8 = 1 4/5 = 9/5
4) 9/5 * 5/9 = 1
5) 27.5 : 1 = 27.5 - первая дробь
6) 6,8 - 3,6 = 3,2 = 3 1/5 = 16/5
7) 16/5 * 5 5/6 = 16/5 * 35/6 = 56/3 = 18 2/3
8) 3 2/3 - 3 1/6 = 3 4/6 - 3 1/6 = 3/6 = 1/2 = 0,5
9) 0,5 * 56 = 28
10) 56/3 : 28 = 2/3 - вторая дробь
11) 27,5 + 2/3 = 27 3/6 + 4/6 = 28 1/6
12) 28 1/6 - 27 1/6 = 1
Ответ: 1