Properties of Real Numbers

What is the missing number?

6 + ____ = 7 + 6

• 4

• 13

• 7

• 9

3 x ____ = 9 x 3

• 7

• 9

• 27

• 11

7 + (4 + 2) = 13, so (7 + 4) + 2

• 10

• 12

• 13

• 14

What is the missing number?

5 × (__× 9) = (5 × 8) × 9

• 5

• 360

• 8

• 9

2 X 0 =

12 X 1 =

What number fills in the blank?
24 + ____ = 24

• 24
• 2
• 0

 $-5+?\ =0$  

 $\frac{1}{7}\times?=1$  

5(a + 6)

• 5a + 6
• a + 30
• 5a + 30
• 5a - 30