):8/13÷7+1/7×6/13 =8/13*1/7+1/7*6/13=1/7[8/13+6/13]=1/7[14/13]=2/132-6/13 ÷9/26-2/3=2-6/13*26/9-2/3=2-4/3-2/3=2-[4/3+2/3]=2-2=0