To get this answer you can divide 321 and 12. But that will give you an uneven number such as 26.75. And because you cant have 26.7 tables you will wound it up to be 27 tables.
since you know that each table can only seat 12 people and there is 321 visitors you divide 321 by 12 which you get 26.75, but u cant have 26.75 tables so you round up to 27 so you can seat all the visitors because if you round down to 26, 9 people won't have a seat.
