Two rectangles B and C, not drawn to scale, overlap at D. D is the shaded area which is
15 of Rectangle B and
19 of Rectangle C. If the length of Rectangle B is 10 cm and its breadth is 5 cm, what is the area of the unshaded part of rectangles B and C?
| |
B |
C |
Difference |
| Total areas |
5 u |
9 u |
4 u |
| Shaded part |
- 1 u |
- 1 u |
|
| Unshaded parts |
4 u |
8 u |
4 u |
The overlapping shaded part of rectangles B and C is the same.
Area of Rectangle B
= 10 x 5
= 50 cm
2 Area of Rectangle B = 5 u
Area of Rectangle C = 9 u
5 u = 50
1 u = 50 ÷ 5 = 10
Area of unshaded parts of rectangles B and C
= 4 u + 8 u
= 12 u
= 12 x 10
= 120 cm
2 Answer(s): 120 cm
2 
