The figure, not drawn to scale, shows a rectangle, BCDE, which is divided in 4 parts, F, G, H, and J. The ratio of the area of J to the area of H is 1 : 3. The ratio of the area of H to the area of G is 4 : 5. If the area of F is 98 cm
2, what is the area of the rectangle BCDE?
J |
H |
G |
F |
1x4 |
3x4 |
|
|
|
4x3 |
5x3 |
|
4 u |
12 u |
15 u |
7 u |
Area H is the repeated identity.
LCM of 3 and 4 = 12
Half of the area of the rectangle
= Area J + Area G
= 4 u + 15 u
= 19 u
Area of F
= Half of the area of the rectangle - Area H
= 19 u - 12 u
= 7 u
7 u = 98
1 u = 98 ÷ 7 = 14
Area of the rectangle
= 19 u x 2
= 38 u
= 38 x 14
= 532 cm
2 Answer(s): 532 cm
2