的分数单位是 ,它含有 个这样的分数单位.再加上 个这样的分数单位就是最小的质数.去掉 个这样的分数单位是1.
4÷5==20÷ = (填小数)
=28: =0.8= ÷10= %= .
=9: = ÷20== %
3:4= :12=12÷ == %
=75÷ =0.75= : = %= 折.