We have 11 large tables with the same number of guess and another table with 5 guess. The number of people on each large table is x, and the total people is T. So the equation is:
The term 11*x represent the people seated in large tables, there are 11 large tables and x people for large table so we multiply 11*x, and the secon term represent the 5 persons in the another table, the sum oof the two terms is the total people.
Finally, if the total number of people=T=82, the value of x is:
We found that there are 7 persons for each large table if the total number of people is 82.