a除b的商是0.875,a与b的比是 ,如果两数的和是30,则b是 .
6÷ = :24==0.75= %.
=75%=9÷ = :20= (填小数)
= ÷20== (在横线上填小数)
3.5== : (最简比).
2: == ÷6== %