1.
Which number sentence shows the commutative property of addition?

a. 9 + 3 = 12

b. 11 + 7 = 7 + 11

c. 3 * 9 = 27

d. 3 + (9 + 1) = (3 + 9) + 1


2.
Use the commutative property to identify which expression is equal to (4 + 7) * 3

a. 4 * 3 + * 3

b. 3 * (4 + 7)

c. (3 * 4 + 7)

d. (4 + 7 * 3)