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by [email protected] » Sun Mar 27, 2016 9:17 pm
Hi kamalakarthi,

I'm going to give you some hints so that you can retry this question on your own:

[spoiler]
1) When the GMAT gives you a 'weird' shape to work with, you should look for any opportunity to 'break down' that shape into shapes that you DO know. Here, you can break each parallelogram down into 2 right triangles and a rectangle.
2) Knowing those 60 degree angles, try breaking down each shape into a 30/60/90 right triangle and a rectangle. What would the sides of the triangle be? Use that information to figure out the dimensions of the rectangle.
3) When you have the area of one parallelogram, you just have to multiply that number by 3 to get the total area of all of the shapes.
[/spoiler]

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by MartyMurray » Sun Mar 27, 2016 9:31 pm
Another key parallelogram concept that may be useful in this case is the fact that the area of a parallelogram = base x height. You know the base. Now how can you use the given angle measure to determine the height?
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by ceilidh.erickson » Mon Mar 28, 2016 3:40 pm
If each line segment is equal to 4, then the figure is composed of three RHOMBUSES (rhombi? I never know how to pluralize that) ;-)

Here is the figure closer to scale:
Image

If each angle is 60 degrees, then each of these shapes can be cut into 2 equilateral triangles:

Image

Simply find the area of an equilateral triangle with a side length of 4:

Image

An equilateral triangle can be chopped into two 30-60-90 triangles. The height = (half of the side length of the equilateral)(sqrt 3)

So the area of the equilateral = (1/2)bh = (1/2)(4)(2√3) = 4√3

Multiply this number by 2 to get the area of each rhombus, then multiply be 3 to get the area of all the shaded figures:
(4√3)(2)(3) = 24√3

The answer is E.
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by kamalakarthi » Mon Mar 28, 2016 4:55 pm
Thanks much for your help. I was able to figure it out the height and calculate the area as well.
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