简算:1+12/6+36/12+80/20+150/30+252/42+392/56+576/72
简算:1+12/6+36/12+80/20+150/30+252/42+392/56+576/72
1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90+1/110=?
7/6+3/12+21/20+31/30+43/42+57/56+73/72+91/90怎样简便运算
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90简便运算怎么做
巧算:1/2+1/6+1/12+1/20+1/30+1/42+1/56=?
1+1∕6+1∕12+1∕20+1∕30+1∕42+1∕56+1∕72
1+2/1-6/5+12/7-20/9+30/11-42/13+56/15-72/17=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20 =
1又1/6+2又1/12+3又1/20+4又1/30+5又1/42+6又1/56+7又1/72 急
5/6-7/12+9/20-11/30+13/42-15/56+17/72,
1/2+1/6+1/12+1/30+1/42