0.25Ⅹ39+0.25
=0.25Ⅹ39+0.25Ⅹ1
=0.25Ⅹ(39+1)
=1/4Ⅹ40
=10
0.25Ⅹ3.2Ⅹ0.125
=0.25Ⅹ4Ⅹ0.8Ⅹ0.125
=1Ⅹ0.1
=0.1