4/3÷6/镇雀7-5/毁旅清6÷6/7=（4/3-5/6）÷6/7=1/纤前2÷6/7=1/2×7/6=7/12
4/3÷6/7-5/6÷6/7=4/3x7/6-5/6x7/6=(4/3-5/6)x7/核闷悔6=(8/改正6-5/6)x7/6=1/2x7/罩态6=7/12
=28/18-35/36=21/36=7/12
