The absolute value is never a negative number; therefore,for the first above question we have
(2009/1-1)+(2010/1-2009/1)+(2011/1-2010/1)
=2010
The second one is quite similar to the first,i.e.
(2/1-1)+(3/1-2/1)+(4/1-3/1)+...+(99/1-98/1)+(100/1-99/1)
=1+1+1+...+1+1
=99
