Answer
The equation described is
(3n/5) + 8 = 15
Step-by-step explanation
Let the number of people in the cafeteria be n
- Each person had 1 friend come sit with them and this tripled the amount.
Number of people in the cafeteria = 3n
- Then, the entire group divided into 5 groups, and all but one group left and went outside, so only 1/5 of the total people were left in the cafeteria.
Number of people left in the cafeteria = (3n/5)
- 8 more people came into the cafeteria.
Number of people left in the cafeteria = (3n/5) + 8
- The total number of people in the cafeteria by the end of lunch was 15.
Number of people left in the cafeteria = (3n/5) + 8 = 15
(3n/5) + 8 = 15
Hope this Helps!!!