的分数单位是 ,它再增加 个这样的单位就等于4;的分数单位是 ,它要变成质数,最少应该减少 个这样的单位.
12÷ =0.75= :32= :20= %= 折.
= :24== %
÷ ═==0.75= : .
= ÷12=18: =2.25=1= %.
=4: = ÷54= (填小数)