平行四边形面积是7平方厘米,与它等底等高的三角形的面积是 .
÷8==0.5= %= : .
=24: = ÷20= %
:20=20: == %= (最后一空填小数)
9÷ ==37.5%=24: =.
3: ==24÷ = %=0.8.