Educator

Properties of Numbers

• To commute means “to change places”; this helps to explain the commutative properties of addition and multiplication: a + b = b + a and a • b = b • a.
• To associate means “to gather in groups”; this helps to explain the associative properties of addition and multiplication: (a + b) + c = a + (b + c) and (a • b) • c = a • (b • c).
• The properties of addition and multiplication often let you do mental computations more easily.
• The Commutative Property, the Associative Property, and the Identity Property apply to both addition and multiplication of rational numbers.