Answer:
17
Step-by-step explanation:
because 12 people can sit at each table, so youd divide 198 by 12 to see how many tables youd need, and you get 16.5. you cant have 16.5 tables, so always round up when it comes to objects, humans, things, etc. so you get 17
3,500,000 - 2,800,000 = 700,000
So the magazine needs 700,000 readers to meet their goal.
Hope that helps you. :-)