(1/4 + 1/12 - 1/16) : ( 2 1/6 - 1 3/8 + 1/12)=
(12+4-3/48):(84-39+2/24)=13/48:47/24=13/48*24/47=13/94
(1/4+1/12-1/16):(2 1/6-1 3/8+1/12)= 1/4+1/12-1/16=12/48+4/48-3/48=13/48 2 1/6-1 3/8+1/12=2-1+4/24-9/24+2/24=1-3/24=24/24-3/24=21/24 13/48:21/24=13/48*24/21=13/42