[60÷（1/2+1/3+1/4+1/5)]÷[5又12/20+3又2/11+11.35—2又5/33）÷5又2/3]
=[(60*60)÷(60*（1/2+1/3+1/4+1/5))]÷[(112/20+35/11+227/20-77/33）* 3/17]
=[3600÷(30+20+15+12)][(339/20+105/33-77/33）* 3/17]
=(3600÷77)[(339/20+28/33）* 3/17]
=3600/77 *[(11747/660）* 3/17]
=3600/77 *(11747/3740）
=180*11747/187*77
=2114460/14399