Which problem demonstrates the associative property? 5.2 (3.1 + 1.9) = (5.2 • 3.1) + (5.2 • 1.9)

5.2 + 1.9 + 3.1 = 10.2

(5.2 + 3.1) + 1.9 = 5.2 + (3.1 + 1.9)

None of the above

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