5 целых7/20++20целых 4/15+12 цэлых 11/60
5 7/20 + 20 4/15 + 12 11/60 = 5 + 20 + 12 + (7/20 + 4/15 + 11/60) = = 37 + (21/60 + 16/60 + 11/60) = 37 + 48/60 = 37 4/5