一道数学题全班40人做对,4人做错,这道题的错误率为 .
==6﹣ = ÷= 折.
:5=72: =18:15== % .
=0.3: = %= (填小数)= 折= 成.
:12= ÷8=0.75== %
÷12=25%=9÷ = : =.