Two rectangles M and N, not drawn to scale, overlap at P. P is the shaded area which is
12 of Rectangle M and
19 of Rectangle N. If the length of Rectangle M is 7 cm and its breadth is 6 cm, what is the area of the unshaded part of rectangles M and N?
| |
M |
N |
Difference |
| Total areas |
2 u |
9 u |
7 u |
| Shaded part |
- 1 u |
- 1 u |
|
| Unshaded parts |
1 u |
8 u |
7 u |
The overlapping shaded part of rectangles M and N is the same.
Area of Rectangle M
= 7 x 6
= 42 cm
2 Area of Rectangle M = 2 u
Area of Rectangle N = 9 u
2 u = 42
1 u = 42 ÷ 2 = 21
Area of unshaded parts of rectangles M and N
= 1 u + 8 u
= 9 u
= 9 x 21
= 189 cm
2 Answer(s): 189 cm
2 
