# Math Course - Properties of Number

Refresher Course in Mathematics - Properties of Number

Number Properties

 Property Definition Examples Closure Property § When we add or multiply any element in a set of numbers, the sum or product is a unique real number which belongs to that same set. 14 + 25 + 44 + 52 = 135 23 x 14 x 10 = 3 220 Commutative Property § states that changing the position of the addends or the factors does not affect the sum or the product 33 + 10 = 10 + 33 18 x 9 = 9 x 18 Associative Property § states that changing the grouping of addends in a sum or the grouping of factors in a product does not change the resulting sum or product (5 + 6) + 7 = 5 + (6 + 7) 2 x (4 x 6) = (2 x 4) x 6 Identity Property Addition § The sum of any number and zero is the same number. § 0 is the identity. 512 + 0 = 512 Multiplication § The product of any number and one is the same number. § 1 is the identity 512 x 1 = 512 Distributive Property of Multiplication over Addition / Subtraction § states that multiplication distributes over addition and subtraction 7(9 + 12) = 7(9) + 7(12)