8,1: 0,4: 2,7*3,06 10,2: 2,4*12,5*0,8

8 1/10: 4/10:2 7/10* 3 6/100=81/4:2 7/10*3 6/100=15/2* 3 6/100=459/20

8,1:0,4:2,7*3,06=51/125
8 1/10:4/10=81/10*10/4=81/4
2,7*3,06=8,262
8 262/1000:81/4=8262/1000*4/81=102/250=51/125
10,2:2,4*12,5*0,8=0,425
2,4*12,5=30
30*0,8=24
10,2:24=0,425