(3 1/6 - 5 1/6 : 4 2/15) : 30 2/3

(3 1/6 - 5 1/6 : 4 2/15) : 30 2/3 = 1/16

1) 5 1/6 : 4 2/15 = 31/6 : 62/15 = 31/6 * 15/62 = (1*5)/(2*2) = 5/4 = 1 1/4
2) 3 1/6 - 1 1/4 = 3 2/12 - 1 3/12 = 2 14/12 - 1 3/12 = 1 целая 11/12
3) 1 11/12 : 30 2/3 = 23/12 : 92/3 = 23/12 * 3/92 = (1*1)/(4*4) = 1/16

Объяснения:
5 целых 1/6 = (5*6+1)/6 = 31/6
4 целых 2/15 = (4*15+2)/15 = 62/15
1 целая 11/12 = (1*12+11)/12 = 23/12
30 целых 2/3 = (30*3+2)/3 = 92/3