1-5/12+8/15+1/12-13/15-29/20
问题描述:
1-5/12+8/15+1/12-13/15-29/20
答
1-5/12+8/15+1/12-13/15-29/20
=1-5/12+1/12+8/15-13/15-1-9/20
=-4/12-5/15-9/20
=-1/3-1/3-9/20
=-(20+20+27)/60
=-67/60
=-1(7/60)