GMAT Data Sufficiency Discussions

amar_sinha_25505345 · June 1, 2009, 6:46am

Isosceles means ONLY 2 sides equal.. and Equilateral means ALL sides equal in length..

Isosceles is NOT same as Equilateral.. or vice versa..

According to me,
All equilateral triangles are isosceles but not the vice versa.
Those isosceles triangle for which the third side is equal to the other two, is equilateral. So equilateral triangle is the special case of isosceles triangle.

nuttyvarun · June 1, 2009, 7:10am

According to me,
All equilateral triangles are isosceles but not the vice versa.
Those isosceles triangle for which the third side is equal to the other two, is equilateral. So equilateral triangle is the special case of isosceles triangle.

You mean just like how square and rectangle are related.. simialr relationship between Isosceles and equilateral triangle.. possible.. 😉

srworld · June 1, 2009, 9:07am

I am not saying Isoscles triangle is equilateral triangle. What am saying is Equilateral triangle is an isosceles triangle with the third angle (first two angles are equal equal) equal to 60.

I can easily put this as a DS question.

I agree that an equilateral triage is an isosceles triangle with its third angle also same as other two. My concern was 'Exactly two of the angles.....'. If the statement says, exactly 2 angles are same, doesn't it mean that its saying 2 and only 2 angles are same. If so then it means its an isosceles triangle and not an equilateral.

ramviswa · June 1, 2009, 3:18pm

You can safely assume that it is an isosceles triangle but cannot conclude that it is not an equilateral triangle.

padmalathas · June 2, 2009, 5:47pm

12769

In triangle ABC, what is the length of BC?

1. AD = 6
2. x = 36

bhavin422 · June 2, 2009, 5:53pm

12769

In triangle ABC, what is the length of BC?

1. AD = 6
2. x = 36

dude...image is too small ...not able to read

..

padmalathas · June 2, 2009, 6:07pm

May be you could right click and open in new window. It is bigger!

bhavin422 · June 2, 2009, 6:08pm

12769

In triangle ABC, what is the length of BC?

1. AD = 6
2. x = 36

Ok ...did manage to read !!

AD=BD=BC

St 1 sufficient....
St 2 : we just have all angles , cant say about the side ...not sufficient...

Hence, Ans A....

padmalathas · June 2, 2009, 6:16pm

Thanks!
But I guess you meant to say AD=BD = 2 BC . Please correct if Im wrong here!

bhavin422 · June 2, 2009, 6:21pm

Thanks!
But I guess you meant to say AD=BD = 2 BC . Please correct if Im wrong here!

nopes ...i did mean AD=BD=BC

Explanation:
We know BD =BC..
By exterior angle theorem,
BDC = DAB+ABD
i.e 2x = x + ABD
Hence, ABD = x

So, AD=BD
Hence, AD=BD=BC...

Hope this helps !!

nuttyvarun · June 2, 2009, 10:03pm

Here's one..
If x and y are both positive integers, how much greater is x than y?

x + y = 20
x = y

I get an answer which is different from the one marked in OG. Share your thoughts!!

nuttyvarun · June 2, 2009, 10:05pm

Here's one..

If x and y are both positive integers, how much greater is x than y?
x + y = 20
x = y
I get an answer which is different from the one marked in OG. Share your thoughts!!

Sorry.. my bad.. I was checking incorrectly.. I also marked the same answer as memtioned in OG...

so no worries.. try this and have fun!! Lemme know if you need any help (though it's pretty simple)

guy_with_guts · June 3, 2009, 4:12am

Sorry.. my bad.. I was checking incorrectly.. I also marked the same answer as memtioned in OG...

so no worries.. try this and have fun!! Lemme know if you need any help (though it's pretty simple)

Originally Posted by nuttyvarun View Post
Here's one..

If x and y are both positive integers, how much greater is x than y?
x + y = 20
x = y
I get an answer which is different from the one marked in OG. Share your thoughts!!

Put the value of x in to the second one
y^2+y=20
y(y+1)=20=4*5
y=4,x=16

C

amar_sinha_25505345 · June 3, 2009, 7:16am

Both the statements are required to give the answer. So the answer is c.

Using both statements, y = -5 or 4. for positive, y = 4.
X = 16.

amar_sinha_25505345 · June 3, 2009, 7:32am

12769

In triangle ABC, what is the length of BC?

1. AD = 6
2. x = 36

First statement alone is sufficient to answer the question.

unbelted · June 4, 2009, 9:35pm

srworld Says
But statement 1 says...Exactly two angles. Doesn't that implies that its saying that only 2 angles measures the same?

Hey!
As the question mentions that "exactly two angles" are same, it is a definite isosceles triangle, without the possibility of being an equilateral.

Had it been specified that "at least two angles" are same, there could have been a possibility of considering it as an equilateral triangle.
Busts the definitions we have been reading since childhood, but hope this helps:

Isosceles Triangle -- from Wolfram MathWorld

Somebody order that beer for me please!

nishantjain1 · June 8, 2009, 7:51am

Hi,

I gave my GMAT in Sep 08; got a 650. Now I am preparing again and wish to reappear by July 09. Wanted to know if there have been any changes in the exam pattern / style of questions / language, etc since then.

Nishant Jain

nuttyvarun · June 8, 2009, 9:29pm

Hi,

I gave my GMAT in Sep 08; got a 650. Now I am preparing again and wish to reappear by July 09. Wanted to know if there have been any changes in the exam pattern / style of questions / language, etc since then.

Nishant Jain

Nishant.. WRONG thread!! ;)

Please post it in GMAT Query or some other thread to get the answer u r looking for!!

shashankaggarwa · June 9, 2009, 8:33am

Hi,

I gave my GMAT in Sep 08; got a 650. Now I am preparing again and wish to reappear by July 09. Wanted to know if there have been any changes in the exam pattern / style of questions / language, etc since then.

Nishant Jain

@Nishant

Kindly use

http://www.pagalguy.com/discussions/gmat-query-center-2008-09-25035266

:cheerio:

nuttyvarun · June 11, 2009, 1:54am

If vmt 0, is v^2m^3t^-4 > 0?
(1) m > v^2
(2) m > t^-4

best luck ;)