a和b都是自然数,已知a×=b÷,则b<a. .
25%=== :20= (填小数)
: =40 =80%= ÷40.
填上适当的数. 7÷13== ÷ ÷7= 9cm=dm.
=12: =0.75= %
= : =27÷ =.