Final answer:
The area of the rectangular floor in square feet is 252.
Step-by-step explanation:
To find the area of the rectangular floor in square feet, we need to multiply the length and width in yards by the conversion factor of 3 feet in 1 yard. The length is 7 yards, so we multiply 7 by 3 to get 21 feet. The width is 4 yards, so we multiply 4 by 3 to get 12 feet. Now, we multiply the length and width in feet to find the area: 21 feet x 12 feet = 252 square feet.