用到乘法分配律简便计算除以25等于乘以1/25
(675-675÷25)÷8
=(675×1-675×1/25)÷8
=675×(1-1/25)÷8
=675×24/25÷8
=675×(24/25÷8)
=675×3/25
=81
(675-675÷25)÷8
=(675-27)÷8
=648÷8
=81
括号里面如果有加减乘除,就先算乘除
原式=[675-(500+100+75)÷25]÷8
=[675-(500÷25+100÷25+75÷25)]÷8
=[675-(20+4+3)]÷8
=(675-27)÷8
=648÷8=81,希望采纳,谢谢。