亿以内数的读法是每级末尾不管有几个0,全都要读出来. .
1: ==25÷ = %=二成.
=40: = ÷40= %= (填小数)
=12: =1.2= ÷20= %
= (填小数)= 折.
÷10=0.25=1: == %.