0.25:十二分之五=1/4:5/12=3:5 比值是0.6
=1/4:5/12=1/4x12/5=3/5=3:53/5
0.25:5/12＝0.25/1:5/12=(12/1*0.25):(12/12*5)=3:5=3/5或0.6
