An 8-by-15-ft wall has three windows. Each window measures 3 ft by 4ft. The area of three windows is what percent of the area of the entire wall (including the windows)?
Wall 8 ft by 15 ft.
Area of wall:
A = 8 ∙ 15 = 120 ft²
Window 3 ft by 4 ft.
Area of window:
Aw = 3 ∙ 4 = 12 ft²
Area of three windows / Area of wall:
3 Aw / A = 3 ∙ 12 / 120 = 3 ∙ 12 / 10 ∙ 12 = 3 / 10 = 0.3
0.3 ∙ 100 % = 30 %
To find the area of the entire wall (including the windows), we will start by finding the area of the wall and then subtracting the area of the windows.
The area of the entire wall can be calculated by multiplying its length by its width:
Area of wall = length x width = 8 ft x 15 ft = 120 sq ft
Next, we need to find the area of the windows. Since there are three identical windows, we will calculate the area of one window and then multiply it by three:
Area of one window = length x width = 3 ft x 4 ft = 12 sq ft
Area of three windows = 12 sq ft x 3 = 36 sq ft
To find the area of the windows as a percentage of the area of the entire wall, we divide the area of the windows by the area of the entire wall and then multiply by 100:
Percentage = (Area of windows / Area of wall) x 100
Percentage = (36 sq ft / 120 sq ft) x 100
Percentage ≈ 30%
Therefore, the area of the three windows is approximately 30% of the area of the entire wall (including the windows).
To find the area of three windows, we first need to calculate the area of one window and then multiply it by three.
One window measures 3ft by 4ft, so its area is 3ft * 4ft = 12 square feet.
Since there are three windows, the total area of the windows is 12 square feet * 3 = 36 square feet.
Now, let's calculate the area of the entire wall. The wall is 8ft by 15ft, so its area is 8ft * 15ft = 120 square feet.
To find the percentage, we divide the area of the windows by the area of the entire wall and then multiply by 100.
Percentage = (Area of the windows / Area of the entire wall) * 100
Percentage = (36 square feet / 120 square feet) * 100
Now let's do the math:
Percentage = (0.3) * 100 = 30%
Therefore, the area of the three windows is 30% of the area of the entire wall.