Final answer:
The example given demonstrates the Associative Property of Addition.
Step-by-step explanation:
The example given, 1/3 + 2/3 + 3/3 = 2/3 + 1/3 + 3/3 = 6/3 = 2, demonstrates the Associative Property of Addition (b).
The Associative Property of Addition states that changing the grouping of numbers being added does not change the sum. In this example, we can group the fractions differently and still get the same result.
For example, we can group the fractions like this: (1/3 + 2/3) + 3/3 = 3/3 + 3/3 = 6/3 = 2. The sum is still 2, reaffirming the property.