8 1/2-3 1/2: (2 1/2 + 1 3/4) •2 3/7= 8 1/2-7/2:(5/2+7/4)*17/7= 8 1/2-7/2:(10/4+7/4)*17/7=
8 1/2-7/2:17/4*17/7=8 1/2-7/2*4/17*17/7=
8 1/2-2=6 1/2
8 1/2-3 1/2: (2 1/2 + 1 3/4) •2 3/7= 8 1/2-7/2:(5/2+7/4)*17/7= 8 1/2-7/2:(10/4+7/4)*17/7=
8 1/2-7/2:17/4*17/7=8 1/2-7/2*4/17*17/7=
8 1/2-2=6 1/2