1.25+0.75*5得简便计算

问题描述:

1.25+0.75*5得简便计算

1.25+0.75*5=0.25*5+0.75*5=(0.25+0.75)*5=1*5=5

1.25+0.75*5
=0.25*5+0.25*15
=0.25*(5+15)
=0.25*20
=5