Question

1997+1-2-3+4+5-6-7+.+1993-1994-1995+1996

Answer 1

1997+1-2-3+4+5-6-7+.+1993-1994-1995+1996

=1-2-3+4+5-6-7+.+1993-1994-1995+1996+1997

=(1-2-3+4)+(5-6-7+8)+.+(1993-1994-1995+1996)+1997

=0+0+0+……+0+1997

=1997