合并同类项:x2y﹣xy2+3x2y﹣xy2= .
÷ == %= : = =七五成.
6:8=3: =12÷ = ÷12=.
÷8=0.75== %= 折.
0.625=== ÷40=40÷ .
在括号里填上适当的数: 25÷32= 1÷ = A÷B= (B≠0)=7÷ ÷9= ÷ = 4==3=2 3=2=1=.