Two rectangles R and S, not drawn to scale, overlap at T. T is the shaded area which is
13 of Rectangle R and
19 of Rectangle S. If the length of Rectangle R is 12 cm and its breadth is 9 cm, what is the area of the unshaded part of rectangles R and S?
| |
R |
S |
Difference |
| Total areas |
3 u |
9 u |
6 u |
| Shaded part |
- 1 u |
- 1 u |
|
| Unshaded parts |
2 u |
8 u |
6 u |
The overlapping shaded part of rectangles R and S is the same.
Area of Rectangle R
= 12 x 9
= 108 cm
2 Area of Rectangle R = 3 u
Area of Rectangle S = 9 u
3 u = 108
1 u = 108 ÷ 3 = 36
Area of unshaded parts of rectangles R and S
= 2 u + 8 u
= 10 u
= 10 x 36
= 360 cm
2 Answer(s): 360 cm
2 
