4 5/12+1 1/2:(6 5/8-3 11/12)x4 1/6
4 5/12+1 1/2:(6 5/8-3 11/12)x4 1/6 6 5/8-3 11/12=3+(15/24-22/24)=3-7/24=2 17/24= 65/24 1 1/2:65/24= 3/2×24//65=36/65 36/65×4 1/6=36/65×25/6=30/13=2 4/13 4 5/12+2 4/13=6+(65/156+48/156=6 113/156=