The Commutative Property states:

 In Addition
the order of the addends 
does not change the sum (answer).

In Multiplication
the order of the factors
does not change the product (answer).

When Adding:

 3 + 4 = 4 + 3
      7 = 7

10 + 7 + 3 = 3 + 7 + 10
20 = 20

(20 + 9) + 2 = (2 + 9) + 20
31 = 31    

When Multiplying:

3 x 5 = 5 x 3
    15 = 15

(6 x 4) x 3 = (3 x 4) x 6
72 = 72

10 x (20 x 9) = (9 x 20) x 10
1,800 = 1,800    

With the Commutative Property,
there can be more than 2 
Addends or Factors...

When Adding:

2 + 5 + 3 = 5 + 3 + 2
   7  +  3 =   8  +  2 
      10    =    10 

(7 + 5) + 4 = (4 + 7) + 5
12 + 4 = 11 + 5
16 = 16

(3 + 6) + 10 = (6 + 10) + 3
9 + 10 = 16 + 3     
   19 = 19           

When Multiplying:

(3 x 6) x 2 = (6 x 2) x 3
    18 x 2 = 12 x 3
         36 = 36

(4 x 5) x 10 = (4 x 10) x 5
20 x 10 = 40 x 5
200 = 200

(2 x 3) x 4 = (3 x 4) x 2
  6 x 4 = 12 x 2    
24 = 24  
        

 REMEMBER :   

Addends or Factors
can change order in a number sentence
and NOT affect the answer