We know width of the room= 15 ft. And we know length of the room= 25 ft. We need to determine the size of the table in order to find the floor space not covered. One each end of the table we have 8 feet. If we subtract the space at both ends of the table and the space on both sides, we'll have the area of the table. We then subtract the area of the table from the area of the room.
STEP 1:
Find area of the room
A= length * width
A= 25 ft * 15 ft
A= 375 ft^2
STEP 2:
Find area of the table by subtracting space around the table from the room's length and width. Remember there are two ends with 8 feet and two sides with 5 feet so we have to multiply by 2.
Table Area= [25 - 2(8)][15 - 2(5)]
= (25-16)(15-10)
= (9)(5)
= 45 ft^2
STEP 3:
Subtract area of table from area of the room
Difference= 375 sqr ft - 45 sqr ft
= 330 sqr ft
ANSWER: D) 330 square feet
Hope this helps! :)