10/11
1-1/6+1/42+1/56+1/72+1/90+1/110
=1-1/6*(1-1/7)+1/56+1/72+1/90+1/110
=1-1/7+1/56+1/72+1/90+1/110
=1-1/7*(1-1/8)+1/72+1/90+1/110
=1-1/8+1/72+1/90+1/110
.(省略了)
=10/11
10/11
1-1/6+1/42+1/56+1/72+1/90+1/110
=1-1/6*(1-1/7)+1/56+1/72+1/90+1/110
=1-1/7+1/56+1/72+1/90+1/110
=1-1/7*(1-1/8)+1/72+1/90+1/110
=1-1/8+1/72+1/90+1/110
.(省略了)
=10/11