It is currently 20 Oct 2017, 07:45

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# M02#20, Error or my confusion? Please need help.

Author Message
Manager
Joined: 05 Jul 2009
Posts: 181

Kudos [?]: 52 [0], given: 5

### Show Tags

27 Oct 2009, 00:33
If $$q$$ is a positive integer, is $$p\frac{q}{\sqrt{q}}$$ an integer?

1. $$q = p^2$$
2. $$p$$ is a positive integer

The Explanation is given as follow:

Statement (1) by itself is sufficient. We know that $$p = \sqrt{q}$$ . Thus $$\sqrt{q}\frac{q}{\sqrt{q}} = q$$ . Since $$q$$ is a positive integer, we have enough information to answer the question.

Statement (2) by itself is insufficient. If $$p$$ is a positive integer, then $$p\sqrt{q}$$ may or may not be an integer, depending on $$q$$ .

Now my question is, how can we say from $$q = p^2$$ that $$p = \sqrt{q}$$?

Say if P=-2 and q=4 (thus $$q = p^2$$). However, -2# $$\sqrt{4}$$. So we need to know whether p is positive or negative. So the answer should be C.

Kudos [?]: 52 [0], given: 5

Intern
Joined: 06 Jul 2009
Posts: 2

Kudos [?]: [0], given: 0

### Show Tags

27 Oct 2009, 02:31
The explanation seems correct if you notice the question asks whether the term is an integer (NOT necessarily a positive integer), hence the explanation seems correct. the only issues is that the step last value should be +/- q and not just q, which is still an integer.
Hope this helps...

Kudos [?]: [0], given: 0

Manager
Joined: 05 Jul 2009
Posts: 181

Kudos [?]: 52 [0], given: 5

### Show Tags

27 Oct 2009, 02:46
mehulsingh wrote:
The explanation seems correct if you notice the question asks whether the term is an integer (NOT necessarily a positive integer), hence the explanation seems correct. the only issues is that the step last value should be +/- q and not just q, which is still an integer.
Hope this helps...

Ohh..thanks very much. I was such a careless $%$&^%!!!

Kudos [?]: 52 [0], given: 5

Re: M02#20, Error or my confusion? Please need help.   [#permalink] 27 Oct 2009, 02:46
Display posts from previous: Sort by

# M02#20, Error or my confusion? Please need help.

Moderator: Bunuel

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.