等底等高的圆柱和圆锥,它们的体积之和是10.8立方分米,那么圆锥的体积是 立方分米.
÷12=1=12: = %
7÷9=,5÷7=.
=15÷ =.
3÷ ==0.375= :24=24: .
=2.5:( )=125%=20÷( )=.