Prealgebra : mathematics for a variable world / Bach, Daniel J. Leitner, Patricia J. Mathematics. 513 HIL 2006 A032 Or. Includes indexes. Boston : McGraw-Hill, c2006. c2006. Text 1 v. (various pagings) : http://www.loc.gov/catdir/enhancements/fy0668/2004056974-d.html http://www.loc.gov/catdir/enhancements/fy0668/2004056974-t.html