1又1/2+2又1/6+3又1/12+4又1/20+5又1/30+……+10又1/110
=1+1/2+2+1/6+3+1/12+4+1/20+5+1/30+……+10+1/110
=(1+2+3+4+5+……+10)+(1/2+1/6+1/12+1/20+1/30+……+1/110)
=(1+10)×10÷2+(1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+……+1/10-1/11)
=55+(1-1/11)
=55+10/11
=55又10/11