1)7/15 : 14/25= 7/15 * 25/14= 7*25/15*14= 175/210=5*35/6*35=5/6
2)8/13 : 4=8/13:4/1= 8/13*1/4=8*1/13*4=8/52=2*4/13*4=2/13
3)9 : 27/28= 9/1 : 27/28= 1/9*28/27=252/27= 38*9/3*9= 28/3= 9 1/3
4) 2 2/9 : 1 7/9=2*9+2/9 : 1*9+7/9= 20/9 :16=20/9*9/16=20*9/9*16=180/144= 5*36/4*36= 5/4=1 1/4
№4 ( 14 - 2 11/12 : 7/18) : 4 7/8
1) 2 11/12 :7/18= 2*12+11/12 : 7/18= 35/12 :7/18= 35/12 * 18/7= 35*18/12*7= 630/84= 15*42/2*42= 15/2= 7 1/2
2) 14 - 7 1/2= 14 - 7 1/2= 14/1 - 7*2+1/2= 14/1 - 15/2= 2*14/2*1 - 1*15/1*2= 28/2 - 15/2= 28*15/2= 13/2=6 1/2
3) 6 1/2 : 4 7/8= 6*2+1/2 :4*8+7/8= 13/2:39/8= 13/2*8/39= 13*8/2*39= 104/78= 4*26/3*26= 4/3= 1 1/3
№5 1 :6= 0,166666666666666