In medium-size bowl, stir together flour, Sweet’N Low, and salt. With pastry blender or two knives used scissor fashion, cut in margarine until mixture resembles coarse crumbs. Add ice water, 1 tablespoon at a time, until mixture just holds together. On lightly floured surface with floured rolling pin, roll out dough into a 10-inch circle. Fit into a 9-inch pie plate. Fold overhang under; make fluted edge.