Answer:
5 people per 42 square feet.
Explanation:
The area of the rectangle is 7 x 12 = 84 square feet.
The ratio of the number of people to the area of the rectangle is:
10 people : 84 square feet
You can simplify this ratio by dividing both sides by 2:
10/2 people : 84/2 square feet
Which can be written as
5 people : 42 square feet