A square ABCD is drawn and point E is marked on AB such that AE=AB/3. Similarly points F, G and H are marked on the sides of the square such than BF=BC/3, CG=DE/3 and DH=DA/3. If the points E, F, G and H are connected to make a parallelogram, what is the ratio of the area of square ABCD to the area of parallelogram EFGH?
A. 81/16
B. 9/4
C. 9/5
D. 5/4
E. 4/5
The OA is C.
Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer. Thanks.
A square ABCD is drawn and point E is marked on AB such...
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swerve wrote:A square ABCD is drawn and point E is marked on AB such that AE=AB/3. Similarly points F, G and H are marked on the sides of the square such than BF=BC/3, CG=DE/3 and DH=DA/3. If the points E, F, G and H are connected to make a parallelogram, what is the ratio of the area of square ABCD to the area of parallelogram EFGH?
A. 81/16
B. 9/4
C. 9/5
D. 5/4
E. 4/5
The OA is C.
Please, can any expert explain this PS question for me? I have many difficulties to understand why that is the correct answer. Thanks.
Let AB = BC = CD = DA = 3.
So AE = BF = CG = DH = 1 and EB = FC = GD = HA = 2.
Hence, Area of triangle AEH = Area of triangle EBF = Area of triangle FCG = Area of triangle GDH = 1/2 * *length * height = 1/2 (2 *1) = 1
Area of all 4 triangles = 4.
Area of square ABCD = AB^2 = 3^2 = 9.
Area of parallelogram EFGH = Area of the square ABCD - the area of all 4 triangles.
Hence, Area of parallelogram EFGH = 9 - 4 = 5.
Hence the ratio of ABCD to EFGH = 9:5.
C