Subtracting One from Another: Numbertime-Addition and Subtraction

Minus Sign (0:47); Passing Down Number Line (1:47); Subtraction Equations (2:34); Ants Doing Math (2:19); Mathematics at Airport (4:12); Song About Subtraction (1:26); Credits: Subtracting One from Another: Numbertime- Addition and Subtraction (0:12);