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MGMAT question
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Cybermusings
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jayhawk2001
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Is it E ?
ABC and DEC are similar triangles. So, AB/DE is some value x.
1 - insufficient. BE = 3 implies DE = 4 but we can't find AB from this
alone
2 - insufficient. Same reason as 1
1 and 2 together don't give you info that 1 alone or 2 alone doesn't
already give you.
Hence E?
ABC and DEC are similar triangles. So, AB/DE is some value x.
1 - insufficient. BE = 3 implies DE = 4 but we can't find AB from this
alone
2 - insufficient. Same reason as 1
1 and 2 together don't give you info that 1 alone or 2 alone doesn't
already give you.
Hence E?
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jayhawk2001
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Actually I think it should be D
There are multiple sets of similar triangles here
ABC and DEC
ABC and BDC
Using ABC and BDC, BD / DE = 5/4 = AB / BD
Since we know BD, we can compute AB.
As mentioned in my earlier post, DE can be computed using 1 or 2.
Hence D
OA please :-)
There are multiple sets of similar triangles here
ABC and DEC
ABC and BDC
Using ABC and BDC, BD / DE = 5/4 = AB / BD
Since we know BD, we can compute AB.
As mentioned in my earlier post, DE can be computed using 1 or 2.
Hence D
OA please :-)
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f2001290
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Remember this formula for similar triangles
Ratio of sides = Ratio of heights = Ratio of Medians = Ration of Angular bisectors = Ratio of In-radius = Ratio of Circum radius.
In the problem, ABC and BDC are similar
so,
Ratio of sides = Ratio of heights
BD/AB = DE/DB
5/AB = 4/5
AB = 25/4
Ratio of sides = Ratio of heights = Ratio of Medians = Ration of Angular bisectors = Ratio of In-radius = Ratio of Circum radius.
In the problem, ABC and BDC are similar
so,
Ratio of sides = Ratio of heights
BD/AB = DE/DB
5/AB = 4/5
AB = 25/4
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Stacey Koprince
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Also remember that any time you have a right triangle and you drop a perpendicular height from the right angle (that is, you create two smaller right triangles out of the right angle of the big triangle), all 3 right triangles will be similar. This problem does so twice, so all of the right triangles are similar.
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Cybermusings
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santosh_surathkal
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Yes OA must be D.Cybermusings wrote:Please solve this DS question...and give detailed explanation!
As 3 right angles are similar we know BE =3 in case 1
and DE = 4 in case 2
if we take case 1 or case 2 individually we can find out all hands of triangle BDE.
Now as triangles are similar we can also find out AB in both the cases.
