1) 12 : 3 3/8 - 1 1/4 : 15/32
1) 12 : 3 3/8= 12 : 27/8= 12* 8/27= (4*8)/9=32/9
2) 1 1/4 : 15/32= 5/4 : 15/32 = 5/4 *32/15=(5*32)/(4*15)=8/3
3) 32/9 - 8/3= (32-24)/9=8/9
2) 1 31/35 :(2- 8/9 : 1 19/45)
1) 8/9: 1 19/45= 8/9:64/45= 8/9*45/64= (8*45)/(9*64)= 5/8
2) 2-5/8= 1 3/8
3)1 31/35 : 1 3/8= 66/35:11/8= 66/35*8/11= (66*8)/(35*11)= 48/35= 1 13/35