Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
19 Dec 2017, 22:16
Kudos
Bookmarks
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
65%
(hard)
Question Stats:
50% (01:39) correct
50%
(02:01)
wrong
based on 270
sessions
History
Date
Time
Result
Not Attempted Yet
If p is a positive integer is √p a positive integer?
1) p is n percentage of n where n is a positive integer
2) p/100 is a positive integer
1) p is n percentage of n where n is a positive integer
2) p/100 is a positive integer
19 Dec 2017, 22:49
Kudos
Bookmarks
(1) p is n% of n, this means p = n/100 * n = (n^2)/100
Here n is a positive integer, so n^2 is a perfect square. And n^2 must be divisible by 100, because then only p will be an integer. Now if we take square root both sides, we have
√p = √(n^2)/ √100 = n/10
Since n^2 is divisible by 100, this means n must be divisible by 10. So √p is an integer. Sufficient.
(2) p is divisible by 100.
If p = 400, then √p = 20 is an integer.
If p = 300, then √p = 10 √3, is not an integer. So Insufficient.
Hence A answer
Here n is a positive integer, so n^2 is a perfect square. And n^2 must be divisible by 100, because then only p will be an integer. Now if we take square root both sides, we have
√p = √(n^2)/ √100 = n/10
Since n^2 is divisible by 100, this means n must be divisible by 10. So √p is an integer. Sufficient.
(2) p is divisible by 100.
If p = 400, then √p = 20 is an integer.
If p = 300, then √p = 10 √3, is not an integer. So Insufficient.
Hence A answer
19 Dec 2017, 23:34
Kudos
Bookmarks
If p is a positive integer is √p a positive integer?
(1) p is n percentage of n where n is a positive integer --> p = n/100*n = (n/10)^2. Now, n is an integer, so n/10 is either an integer or a fraction but since p is an integer and fraction^2 cannot be an integer, then n/10 can only be an integer, thus p = (n/10)^2 = integer^2. Sufficient.
(2) p/100 is a positive integer. If p = 100, then the answer is YES but if p = 200, then the answer is NO. Not sufficient.
Answer: A.
Hope it's clear.
(1) p is n percentage of n where n is a positive integer --> p = n/100*n = (n/10)^2. Now, n is an integer, so n/10 is either an integer or a fraction but since p is an integer and fraction^2 cannot be an integer, then n/10 can only be an integer, thus p = (n/10)^2 = integer^2. Sufficient.
(2) p/100 is a positive integer. If p = 100, then the answer is YES but if p = 200, then the answer is NO. Not sufficient.
Answer: A.
Hope it's clear.
