Regrouping
11
57
 +68 
125

11
125
-57
68

Links

http://www.youtube.com/watch?v=5SZfXi_44Rg


http://www.mathplayground.com/howto_regroupI.html

http://www.mathsisfun.com/numbers/subtraction-regrouping.html

http://www.dositey.com/2008/addsub/subra4.htm

http://abcteach.com/directory/basics/math/regrouping/

http://mathforum.org/library/drmath/sets/select/dm_borrow.html

http://www.myschoolhouse.com/courses/O/1/40.asp

http://www.eduplace.com/math/mw/models/overview/2_10_3.html

http://www.eduplace.com/math/mw/models/overview/2_12_3.html