Data Sufficiency Problem-Solving for x

This topic has expert replies
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Sun Jan 07, 2007 3:31 pm
Location: Michigan

Data Sufficiency Problem-Solving for x

by jd6199 » Sat Jan 20, 2007 11:17 am
SOURCE: PEARSON PRACTICE GMAT TEST 1

IS X BETWEEN 0 and 1?

1. X is between -1/2 and 3/2
2. 3/4 is 1/4 more than x

Answer is B. But I dont understand why statement 1 could not be a solution

Junior | Next Rank: 30 Posts
Posts: 24
Joined: Sun Jan 07, 2007 6:14 pm
Thanked: 1 times

by Argen » Thu Mar 01, 2007 2:47 pm
Considering statement 1, x could be larger than 1 or smaller than 0, so itself alone is insufficient.

Junior | Next Rank: 30 Posts
Posts: 17
Joined: Thu Jul 05, 2007 9:08 am
Location: Kingston, Jamaica

Isn't this a Yes or No Question?

by jcan-gmatter » Tue Jan 08, 2008 11:58 pm
Is this a YES or NO DS question?

Based on the information supplied in 1, the answer is NO, cause X could be -0.3 which is less than 0 or 1.3 which is greater than 1.

Based on the information supplied in 2, the answer is YES cause X = 1/2, which is between 0 and 1.

So, shouldn't the answer be D -> each statement alone is sufficient?

Regards,
Andrew

Senior | Next Rank: 100 Posts
Posts: 33
Joined: Tue Dec 04, 2007 12:04 pm
Location: Nova Scotia
Thanked: 6 times

by Tud » Wed Jan 09, 2008 9:07 am
It's a yes or no question, and statement 1 is insuff because x could be -0.3, which would be no, or it could be 0.5, which is yes. So statement 1 on it's own is insuff to answer the yes or no question.

Answer B

Senior | Next Rank: 100 Posts
Posts: 49
Joined: Sun Jan 13, 2008 10:47 pm
Thanked: 1 times

by desihokie » Tue Jan 15, 2008 12:35 am
B is the right answer.

the question can be asked in another way as: Is X positive?

1. -1/2<X<3/2, which means X could be -ve (-0.4) or positive (0.5), insufficient to answer the question.

2. 3/4-1/4 = X, which means, X=1/2, sufficient