求一个小数的近似数,如果保留三位小数,要看小数的 位.
6÷ ==37.5%=12: =.
=12÷ =0.25=4: = %
1÷4==4: = %= (小数)
==6﹣ = ÷= 折.
:5=72: =18:15== % .