BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

points in the plane

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 87
Joined: Sun Apr 19, 2009 11:07 pm

points in the plane

by success1111 » Tue May 05, 2009 1:11 am
S is a set of points in the plane. How many distinct triangles can be drawn that have three
of the points in S as vertices?

(1) The number of distinct points in S is 5.
(2) No three of the points in S are collinear.
Trust but verify.
Top
Source: — Data Sufficiency |
Master | Next Rank: 500 Posts
Posts: 418
Joined: Wed Jun 11, 2008 5:29 am
Thanked: 65 times

by bluementor » Tue May 05, 2009 1:57 am
You can draw a triangle if you have three distinct points that do not all lie on the same line. For example, if you have (0,0), (1,1) and (1,0), we can draw a triangle. However, if you have (0,0), (1,1) and (2,2), then you CANNOT draw a triangle since all these points lie on a single straight line.

Statement 1: 5 distinct points in set S.

We do not know if these 5 points (or at least 3 of these) lie on a single straight line. Insufficient.

Statement 2: No three of the points in S are collinear.

I believe this means no three points form a straight line. However, we don't know the number of distinct points in set S. Insufficient.

Both statements together: We know the number of distinct points, and we also know that no three points lie on the same line. Sufficient.

Choose C.

-BM-
Top
Senior | Next Rank: 100 Posts
Posts: 87
Joined: Sun Apr 19, 2009 11:07 pm

by success1111 » Tue May 05, 2009 2:12 am
bluementor wrote:You can draw a triangle if you have three distinct points that do not all lie on the same line. For example, if you have (0,0), (1,1) and (1,0), we can draw a triangle. However, if you have (0,0), (1,1) and (2,2), then you CANNOT draw a triangle since all these points lie on a single straight line.

Statement 1: 5 distinct points in set S.

We do not know if these 5 points (or at least 3 of these) lie on a single straight line. Insufficient.

Statement 2: No three of the points in S are collinear.

I believe this means no three points form a straight line. However, we don't know the number of distinct points in set S. Insufficient.

Both statements together: We know the number of distinct points, and we also know that no three points lie on the same line. Sufficient.

Choose C.

-BM-
BM,
Thanks a lot for your response.OA is C. This will definitely help.
Trust but verify.
Top
Post new topic Post Reply
• Page 1 of 1