1) 3 3/4:3/8:1 3/7=15/4:3/8:10/7=15/4*8/3*7/10=7
2) 3 3/4:(3/8:1 3/7)=15/4:(3/8:10/7)=15/4:(3/8*7/10)=15/4:21/80=15/4*80/21=
100/7=14 2/7
3) 1 7/9*15/32:1 19/36=16/9*15/32:55/36=5/6*36/55=6/11
4) 1 7/9*(15/32:1 19/36)=16/9*(15/32:55/36)=16/9*(15/32*36/55)=16/9*108/352
=12/22=6/11
5) 3 4/7:1 1/7*2/3=25/7:8/7*2/3=25/7*7/8*2/3=25/12=2 1/12
6) 3 4/7:(1 1/7*2/3)=25/7:(8/7*2/3)=25/7:16/21=25/7*21/16=75/16=4 11/16