小学数学怎样简算：1/1x2+1/2x3+1/3x4+1/4x5
怎样简算： 1/1x2+1/2x3+1/3x4+1/4x5+...+1/98x99+1/99x100
1/1x2+1/2x3+1/3x4+1/4x5+...+1/98x99+1/99x100 =1-1/2+1/2-1/3+1/3-1/4+……1/98-1/99+1/99-1/100 =1-1/100 =99/100