(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 11/12

3) 1 11/12 : 30 2/3 = 23/12 : 92/3 = 23/12 · 3/92 = (1·1)/(4·4) = 1/16

ответ: 1/16.