Which property of addition is shown by 7 3 5 7 3 5?

Well, honey, those numbers are just showing the commutative property of addition - it doesn't matter what order you add them in, the sum remains the same. So whether you add 7 + 3 + 5 or 5 + 3 + 7, you still end up with 15. Math is like a good recipe, as long as you follow the steps, you'll get the right result.