Step-by-step explanation: First you subtract 16.90 by 11.50 which gives you $5.04 Next, you divide $5.04 by the amount of friends there are (3) Then that gives you the total of $1.68 total cost for drinks.
You can multiply 16 times what equls 88 and then divide by 4 much more simple than it sounds and also your in high school and u cant solve this problem