用简便方法计算:0.25*39*0.25
问题描述:
用简便方法计算:0.25*39*0.25
答
0.25×39+0.25
=1/4×(39+1)
=0.25×40
=10
0.25×39×0.25
=1/4×1/4×39
=1/16×39
=39/16