Question

For Monica’s 14th birthday, she wants to make over her bedroom. The first phase in the bedroom makeover is painting her room. 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, including the floor and ceiling(1 point)
surface area =
square feet
Remaining Attempts : 3

Answer 1

To find the surface area of Monica's room that needs to be painted, we need to calculate the surface area of the walls, ceiling, and floor.

**Step 1: Calculate the area of the floor and ceiling.**

The floor and ceiling are both rectangles with the same dimensions.

- Length = 20 ft
- Width = 15 ft

Area of the floor (or ceiling) = Length × Width = 20 ft × 15 ft = 300 sq ft

Since there are both a floor and a ceiling:

Combined area of the floor and ceiling = 2 × Area of one = 2 × 300 sq ft = 600 sq ft

**Step 2: Calculate the area of the four walls.**

- Two walls will have dimensions of 20 ft (length) × 9 ft (height)
- The other two walls will have dimensions of 15 ft (width) × 9 ft (height)

Area of the two length walls:
\[
2 \times (20 ft \times 9 ft) = 2 \times 180 sq ft = 360 sq ft
\]

Area of the two width walls:
\[
2 \times (15 ft \times 9 ft) = 2 \times 135 sq ft = 270 sq ft
\]

**Total area of the walls**:
\[
360 sq ft + 270 sq ft = 630 sq ft
\]

**Step 3: Calculate the total surface area to be painted.**

Total surface area = Area of the floor and ceiling + Total area of the walls
\[
600 sq ft + 630 sq ft = 1230 sq ft
\]

So, the total surface area that will be painted is:
\[
\text{Surface area} = 1230 \text{ square feet}
\]