The rectangle is divided into four parts G, H, J and K. The ratio of Part G to Part H is 6 : 1 and the ratio of Part H to Part J is 3 : 1.
- Find the ratio of Part G to Part H to Part J.
- Given that Part K is 100 m2 , find the area of the rectangle.
(a)
| G |
H |
J |
K |
| 6x3 |
1x3 |
|
|
| |
3x1 |
1x1 |
|
| 18 u |
3 u |
1 u |
100 m2 |
Part H is the repeated identity.
LCM of 1 and 3 = 3
Part G : Part H : Part J = 18 : 3 : 1
(b)
Part G + Part H = Half of the rectangle
Part J + Part K = Half of the rectangle
Part G + Part H and Part J + Part K are equal.
Part G + Part H = Part J + Part K
18 u + 3 u = 1 u + 100
18 u + 3 u - 1 u = 100
20 u = 100
1 u = 100 ÷ 20 = 5
Area of the rectangle
= 2 x (1 u + 100)
= 2 x (1 x 5 + 100)
= 2 x (5 + 100)
= 2 x 105
= 210 m
2 Answer(s): (a) 18 : 3 : 1; (b) 210 m
2 
