What mathematical property is illustrated by turnaround facts?

Turnaround facts demonstrate the commutative property of addition. This property states that the order in which two numbers are added does not affect the sum. For example, if you take the numbers 3 and 5, the turnaround facts would show that 3 + 5 = 8 and 5 + 3 = 8. Both expressions yield the same result, thereby illustrating that the placement of the numbers can be swapped without changing the outcome.

The other mathematical properties mentioned do not pertain to turnaround facts. The associative property deals with how numbers are grouped in addition or multiplication, the distributive property relates to distributing multiplication over addition, and the identity property refers to an operation that leaves a number unchanged (like adding 0 or multiplying by 1). Therefore, the essence of turnaround facts lies in their demonstration of the commutative property.