把一根木料锯成5段,每锯一次所用的时间是总时间的. .
=12÷ =0.25=4: = %
1÷4==4: = %= (小数)
==6﹣ = ÷= 折.
:5=72: =18:15== % .
=0.3: = %= (填小数)= 折= 成.