草场上有一个长20米、宽10米的关闭着的羊圈,在羊圈的一角用长30米的绳子拴着一只羊(如图).问:这只羊能够活动的范围有多大?
= :24=5:8= :40= %
3÷ ==0.75=6: = %
3÷ ==0.6=6: = %.
3:5==9: == .
=0.375=12÷ = %=0.45= %= ÷ .