Answer: 2
In this case, every student is served 2/3 cup of lemonade and Alex has 1 1/3 cups of lemonade left. Then you just need to divide the lemonade left with lemonade served per student. The calculation would be:
Number of students served= lemonade left / lemonade served per student
Number of students served= 1 1/3 cup / (2/3 student/cup) = 2 student
