The correct interpretation from the provided statements is:
Statement #1: Sarah spends $50.00 per t-shirt.
In the expression 50x + 30y, the coefficient 50 represents the cost per t-shirt (where x is the number of t-shirts), and the coefficient 30 represents the cost per hat (where y is the number of hats). Thus, Statement #1 accurately reflects the cost per t-shirt.
Statement #2 is incorrect because it describes the cost per hat instead of per t-shirt. Statement #3 is also incorrect because the expression represents total spending, not just the total for t-shirts.