在横线上填上“>”“<”或“﹦”.0.687 0.684.8 4.481.4 1.9.0 9..
3.5==( )÷6=( ):( )最简比.
÷40= = :16= %=0.375.
= ÷48.
== ÷ .
=18: = :20== ÷40= [填小数].