叫直径,直径是 的2倍.
=______÷______=60%=______:______=______小数.
2.5:______==1.25=25÷______=______%.
3:5==15÷______=______÷75=______(填小数)
4:10==20÷______="______" (填小数).
0.5÷______==2:______。