parallelo

This topic has expert replies
Legendary Member
Posts: 1578
Joined: Sun Dec 28, 2008 1:49 am
Thanked: 82 times
Followed by:9 members
GMAT Score:720

parallelo

by maihuna » Wed Jan 21, 2009 10:44 am
In the quadrilateral PQRS, side PS is parallel to side QR. Is PQRS a parallelogram?

(1) PS = QR

(2) PQ = RS
Source: — Data Sufficiency |

User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 am
Thanked: 712 times
Followed by:550 members
GMAT Score:770

by DanaJ » Wed Jan 21, 2009 11:35 am
I pretty sure that stmt 2 by itself is not sufficient, since I immediately thought of an isosceles trapezoid with PQ and SR as the un-parallel sides. But I cannot think of an explanation for why stmt 1 is enough.... Although I'm confident it has to do with the angles that the two parallel sides create with a digonal that, together with the lengths of the sides, make similar triangles...

Junior | Next Rank: 30 Posts
Posts: 28
Joined: Sun Nov 02, 2008 12:35 pm
Thanked: 7 times

by sachinkr » Wed Jan 21, 2009 12:22 pm
IMO the ans is A

Given PQRS is qualilateral whose sides PQ || RS.
We need to find whether PQRS is a parallelogram?

A: PQ = SR, Sufficient (Condition for parallelogram is 2 opposite sides of quadilateal are parallel and equal)

B: PS = QR , not sufficient as mentioned by DanaJ.

Newbie | Next Rank: 10 Posts
Posts: 2
Joined: Sat Mar 28, 2009 7:34 pm

by Freedom007 » Wed Apr 29, 2009 7:49 am
but PQRS can very easily be a square and still satisfy statement (1) so why is the answer not E?

Master | Next Rank: 500 Posts
Posts: 424
Joined: Sun Dec 07, 2008 5:15 pm
Location: Sydney
Thanked: 12 times

by piyush_nitt » Wed Apr 29, 2009 3:14 pm
Freedom007 wrote:but PQRS can very easily be a square and still satisfy statement (1) so why is the answer not E?
Square is a ||gram.