Answer:
50% off deal is better.
Explanation:
Given : Deal 50% off or buy one, get one at half price.
To find : Which is a better deal on a $7.99 item ?
Solution :
The cost of item is $7.99.
Deal 50% off,
The cost of item became,
The cost of item at deal 50% off is $3.995.
Deal buy one, get one at half price,
The cost of item became,
The cost of one item is $7.99.
The cost of second item is half of one i.e.
Total cost of two item is
The cost of one item became
The cost of item at deal buy one, get one at half price is $5.9925.
As 5.9925 > 3.995
Deal of buy one, get one at half price cost more than 50% off deal.
Therefore, 50% off deal is better.