Geometry

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by nisagl750 » Tue Nov 27, 2012 9:20 am
SammyJaggi wrote:2 squares of 6 cm intersect each other to form a regular octagon,find the perimeter of regular octagon
What are the options? we can arrange the answer in the required form.

IMO [spoiler]Perimeter is 24/(sqrt2 + 1)[/spoiler]
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by Bill@VeritasPrep » Tue Nov 27, 2012 10:42 am
SammyJaggi wrote:2 squares of 6 cm intersect each other to form a regular octagon,find the perimeter of regular octagon
Is 6cm the area? Perimeter? Side length?
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by nisagl750 » Tue Nov 27, 2012 10:46 am
Bill@VeritasPrep wrote:Is 6cm the area? Perimeter? Side length?
I Missed that.....took 6 as side.

Is my answer correct Bill?

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by Bill@VeritasPrep » Tue Nov 27, 2012 11:18 am
nisagl750 wrote:
Bill@VeritasPrep wrote:Is 6cm the area? Perimeter? Side length?
I Missed that.....took 6 as side.

Is my answer correct Bill?
I think it is almost certainly the side, but I've seen stranger things on GMAT problems :D

I set it up the same way you did, but your diagram is a lot cleaner than mine. The key is figuring out that we end up with 45:45:90 triangles around the outside of the octagon, as you did.
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