大圆的半径与小圆的直径的比是1:1,则大圆的面积与小圆的面积的比是 .
10÷ == : = (小数)= %
:20==24÷ =80%
3:4==24÷ = %= .(填小数)
75÷ == .
= :10=0.2=10÷ = %.