①3/4×7/8÷0.75 ②（2/5-3/8)×40 ③2/7-9/16×2/7
问题描述：
①3/4×7/8÷0.75 ②（2/5-3/8)×40 ③2/7-9/16×2/7
求这三道的简便算式
要算式
答
①3/4×7/8÷0.75
=(3\4÷0.75 )x7\8
=(3\4÷3\4)x7\8
=7\8
②（2/5-3/8)×40
=2\5x40-3\8x40
=16-15
=1
③2/7-9/16×2/7
=2\7x(1-9\16)
=2\7x7\16
=1\8