Mia's birthday party will cost $12 if she invites 4 guests. What is the maximum number of guests there can be if Mia can afford to spend a total of $15 on her birthday party?
You find how much each person costs so 12/4 = 3. So every person costs 3 dollars. Then you divide 15/3 and you get 5 so she can invite a max of 5 people
