Answer:
The brand that sells each individual shirt for $8.25. You will only have to spend $41.25 if you that way for five shirts and for 8 shirts you would only spend $66 when the competitor would have you pay 70$ for 8 shirts.
Step-by-step explanation
First: Multiply $8.25 by five and you'll get $41.25.
Second: Multiply $8.25 by 8 and you'll get $66.
Therefore it is cheaper to buy from the first company. Not the competitor.