You and your cousin go out to eat and you both have the same taste today and order the same item. You both order the $9 item and
both have a $2.50 side item. You receive 50% off your entire bill! You then pay 10% tax on your new discounted bill. What does the bill end up costing you without tip?
The total of just you and your cousin's meals would be $23. Then taking 50% off would be $11.50. Lastly, with the 10% tax, that would make it $12.65. Sorry if I get it wrong.