(5 3/5):(2 1/10) = ((25+3)/5):((20+1)/10) = (28/5):(21/10)
= (28*2/(5*2)):(21:10) = (56/10):(21/10) = 56:21
= (7*8):(7*3) = 8:3
= (28*2/(5*2)):(21:10) = (56/10):(21/10) = 56:21
= (7*8):(7*3) = 8:3