甲数是40,乙数是50,甲数比乙数少( )%,乙数比甲数多( )%。
= ÷ 29÷18= 0.15= .
3:4=12: = :12= %
12÷ == ÷45.
9: ==3÷5.
3÷4==27: = (填小数)= %.