решение по действиям:
1) 4 1/6 + 1,25 = 4 1/6 + 1 25/100 = 25/6 + 1 1/4 = 25/6 + 5/4 = 50/12 + 15/12 = 65/12
2) 3,5 - 1 1/3 = 3 5/10 - 4/3 = 3 1/2 - 4/3 = 7/2 - 4/3 = 21/6 - 8/6 = 13/6
3) 65/12 : 13/6 = 65*6/12*13 = 65/26 = 5/2
4) 2,6-1 2/3 = 2 6/10 - 5/3 = 2 3/5 - 5/3 = 13/5 - 5/3 = 39/15 - 25/15 = 14/15
5) 0,2 + 1/30 = 2/10 + 1/30 = 6/30 + 1/30 = 7/30
6) 14/15 : 7/30 = 14*30/15*7= 4
7) 5/2 * 4= 5/2* 3 2/2 = 5/2 * 8/2 = 40/4 = 10
8) 10*3,2 = 32
9) 7/12 - 0,375 = 7/12 - 375/1000 = 7/12 - 3/8 = 14/24 - 9/24 = 5/24
10) 0,85 : 5/24 = 17/20 : 5/24 = 17*24 / 20*5 = 408/100 = 4 2/25
11) 408/100 - 0.08 = 408/100 - 8/100 = 400/100 = 4
12) 32:4 = 8