Mathematics, Operations (+, -, x, /, etc.), Problem Solving
Grade 3- 5
Students learn about the Commutative and Associative Properties of Multiplication.
Facts to Know
Commutative Property
The Commutative Property of Multiplication states that when the order of the factors is changed, the product stays the same. Multiplication is a commutative operation. In the equation 2 x 4 = 4 x 2, for example, the order of the factors does not affect the answer
(4 x 2 = 8 and 2 x 4 = 8).
The commutative property works for any number of factors. Study the following samples:
Sample A
5 x 6 x 7 = 7 x 6 x 5
5 x 6 x 7 = 210
7 x 6 x 5 = 210
Sample B
70 x 90 = 6,300
90 x 70 = 6,300
Sample C
30 x 50 = 50 x 30
30 x 50 = 1,500
50 x 30 = 1,500
Associative Property
The Associative Property of Multiplication states that when the grouping of the factors is changed, the product stays the same. Multiplication is associative. The way the factors are grouped with parentheses does not affect the answer. Study the following samples:
Sample D
2 x (3 x 4) = (2 x 3) x 4
2 x (3 x 4) = 24
(2 x 3) x 4 = 24
Sample E
6 x (7 x 9) = (6 x 7) x 9
6 x (7 x 9) = 378
(6 x 7) x 9 = 378
Sample F
4 x (5 x 6) = (4 x 5) x 6
4 x (5 x 6) = 120
(4 x 5) x 6 = 120
Distribute the activity sheets to students and have them use their knowledge of these properties to solve the problems.