(3 1/4 + 1 1/6 : 1 5/9) : 2 2/7 + 5 1/9 : 7 2/3 = 2 целых 5/12
1) 1 1/6 : 1 5/9 = 7/6 : 14/9 = 7/6 * 9/14 = (1*3)(2*2) = 3/4
2) 3 1/4 + 3/4 = 3 4/4 = 4
3) 4 : 2 2/7 = 4 : 16/7 = 4 * 7/16 = 7/4 = 1 3/4
4) 5 1/9 : 7 2/3 = 46/9 : 23/3 = 46/9 * 3/23 = (2*1)/(3*1) = 2/3
5) 1 3/4 + 2/3 = 1 9/12 + 8/12 = 1 17/12 = 2 5/12