(2целых 4/15 - 1 целая 5/12) : 3 Целых 2/5+ 1/8=
(2 4/15-1 5/12):3 2/5+1/8=3/8 34/15-17/12=51/60 51/60:3 2/5=51/60:17/5=3/12=1/4 1/4+1/8=3/8