Solution:
Case: Area
Given: A house to be painted
Method/ Final answers
a) Find the area of the garage to be painted.
(i) Front.
A = l X w - Garage door area
l= 15 ft, b= 10-4 gives 6ft
A= 15 X 6 - (10 X 7)
A= 90 - 70
A= 20 square feet
ii) Side
A= l X w
A= 6 X 5
A= 30 square feet
iii) The sum of areas
A= 20 + 30
A= 50 square feet
b) Area of the painted region around windows 5 and 6.
Since 12 in = 1 ft
Area of front door converted to feet is (20/3) ft by 3 ft
Areas of windows 5 and 6 converted to feet is 3 ft by (5/3) ft each
A= Area of space - (Area of front door + window 5 + window 6)
A= (30 X 10) - [(20/3) X 3 + 3 X (5/3) + 3 X (5/3)]
A= 300 - [20 + 5 + 5]
A= 300 - 30
A= 270 square feet.
c) Area of the painted region around windows 3
A= Total face - Area of window 3
A= (Rectangle + Parallelogram + Triangle) - Area of window 3
A= [(10 X 4) + (5 X 4) + (0.5 X 4 X 3)] - [1 X (5/3)]
A= [40+20+6] - [5/3]
A= 66 - (5/3)
A= 193/3 square feet
A= 63.33 square feet
d) Area of the region on the second floor with 2 rectangles and the region around window 4
i) region with rectangle 1 from left to right
A= 10 X (15- 6)
A= 10 X 9
A = 90
ii) region with rectangle 2 from left to right
A= 10 X (15- 6)
A= 10 X 9
A = 90
iii) Area of region around window 4
Area of space - area of window
A= 10 X (30-9-12) - [3 X (5/2)]
A= 10 X 9 - (15/2)
A= 82.5.
Total area= 90 + 90 + 82.5
= 262.5 square feet
e) Total area of the painted region (white)
262.5 + 63.33+ 270 + 50
= 645.83 square feet.
f) Additional question
The total cost if it cost $8 per sq ft
645.83 square feet X $8 per sq ft
=$5166.64