If Monica's room is 20 ft long, 15 ft wide, and 9 ft high, find the surface area of the room that you are going to paint (For this question, pretend that you are painting ALL surfaces inculding the floor and ceiling)
Surface Area of a Rectangular Prism: 2lw + 2lh + 2wh
First, calculate the surface area of the walls:
2lw + 2lh + 2wh
= 2(20*15) + 2(20*9) + 2(15*9)
= 2(300) + 2(180) + 2(135)
= 600 + 360 + 270
= 1230 square feet
Now, add the surface area of the floor and ceiling:
= 20*15 + 20*15
= 300 + 300
= 600 square feet
Total surface area to be painted: 1230 + 600 = 1830 square feet
Therefore, the surface area of the room that needs to be painted, including the floor and ceiling, is 1830 square feet.