The figure is made up of two squares and a triangle. The ratio of the area of Triangle L to that of Square N is 7 : 1. The ratio of the shaded area to that of the unshaded area is 1 : 5. If the difference between areas of Triangle L and Square M is 638 cm
2, what is the area of Square N?
Area of Triangle L |
Area of Square N |
Shaded area |
Unshaded area |
Total area |
7x6 |
1x6 |
|
|
7x6 |
|
|
1x7 |
5x7 |
6x7 |
42 u |
6 u |
7 u |
35 u |
42 u |
Area of Triangle L = Total area of the figure
Total area is the unchanged total. Make the total area the same.
LCM of 7 and 6 = 42
Area of Square M
= 7 u + 6 u
= 13 u
Difference between the areas of Triangle L and Square M
= 42 u - 13 u
= 29 u
29 u = 638
1 u = 638 ÷ 29 = 22
Area of Square N
= 6 u
= 6 x 22
= 132 cm
2 Answer(s): 132 cm
2