To find out how much the stadium paid for the T-shirts given away, you can multiply the cost of each T-shirt by the number of T-shirts given away.
The cost of each T-shirt is $15.00, and the number of T-shirts given away is 100.
Calculation: \( 100 \text{ T-shirts} \times 15 \text{ dollars per T-shirt} = 1500 \text{ dollars} \)
So, the stadium paid $1,500.00 for the T-shirts it gave away.