Compare 1-1 / 2 + 1 / 3-1 / 4 +1 / 1997-1 / 1998 + 1 / 1991 and 1 / 1000 + 1 / 1001 + +The size of 1 / 1998 + 1 / 1999

Compare 1-1 / 2 + 1 / 3-1 / 4 +1 / 1997-1 / 1998 + 1 / 1991 and 1 / 1000 + 1 / 1001 + +The size of 1 / 1998 + 1 / 1999

1/1000+1/1001+… +1 / 1998 + 1 / 1999