如图所示,阴影部分面积是10×l0÷2÷2=25平方单位. .(判断对错)
18÷ ==0.9:0.3=3: = :24.
÷15=0.8==16: = %= 折.
0.8==12÷ = 折= %
3÷ == :12=七成五= %
=0.75=15÷ .