Last visit was: 07 May 2024, 03:30 It is currently 07 May 2024, 03:30

Close
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
Your Progress

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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
SORT BY:
Date
Tags:
Show Tags
Hide Tags
Math Expert
Joined: 02 Sep 2009
Posts: 93072
Own Kudos [?]: 621828 [11]
Given Kudos: 81780
Send PM
Verbal Forum Moderator
Joined: 08 Dec 2013
Status:Greatness begins beyond your comfort zone
Posts: 2100
Own Kudos [?]: 8825 [3]
Given Kudos: 171
Location: India
Concentration: General Management, Strategy
GPA: 3.2
WE:Information Technology (Consulting)
Send PM
Current Student
Joined: 13 Apr 2015
Posts: 1436
Own Kudos [?]: 4552 [0]
Given Kudos: 1228
Location: India
Send PM
User avatar
Manager
Manager
Joined: 02 Jun 2015
Posts: 61
Own Kudos [?]: 61 [0]
Given Kudos: 14
Location: Brazil
Concentration: Entrepreneurship, General Management
GPA: 3.3
Send PM
Re: If P and Q are positive integers, is the product 3P^Q divisible by 2? [#permalink]
1-> We cannot say anything, we don't have the value of P

2-> P + 8Q^2 is a prime number
This means that the number has to be odd
8Qˆ2 is always even.
Therefore P has to be ODD.

Now if we look at the first equation 3P^Q
It doesn't matter how many times we are going to multiple the P, its always going to be Odd:
Odd*Odd=Odd
It means that we cannot divide it by 2

Answer B
avatar
Intern
Intern
Joined: 01 Dec 2015
Posts: 3
Own Kudos [?]: 1 [0]
Given Kudos: 2
Send PM
Re: If P and Q are positive integers, is the product 3P^Q divisible by 2? [#permalink]
Here P and Q are positive integers, and we are asked that whether \(3P^Q\) is even or not?

Now we are basically concerned with P i.e. is P even or not?
Because 3 multiplied by even is even and any power to even no. gives you even result.

Statement 1 says: \(6Q^3+2\) is even, but we do not know anything about P.

therefore insufficient.

Statement 2 says : \(P+8Q^2\) is prime.
Now this Prime must be greater than 2, because both P and Q are Positive Integers.
Now, rest all Primes are odd. Therefore,

Odd-\(8Q^2\) will give odd result. Therefore P is Odd.

Therefore sufficient.

Thus, answer is B
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 10156
Own Kudos [?]: 16652 [1]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Send PM
Re: If P and Q are positive integers, is the product 3P^Q divisible by 2? [#permalink]
1
Kudos
Expert Reply
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.

If P and Q are positive integers, is the product 3P^Q divisible by 2?

(1) 6Q^3 + 2 is an even number
(2) P + 8Q^2 is a prime number

The question is eventually asking whether P is even as 3 cannot be divided by 2.
From condition 2, p+8Q^2 is told to be prime and this means p is odd, so this answers the question 'no' and is therefore sufficient.
From condition 1, the question is asking whether P is even so this is irrelevant to the question, and insufficient.
The answer therefore becomes (B).

Once we modify the original condition and the question according to the variable approach method 1, we can solve approximately 30% of DS questions.
User avatar
Non-Human User
Joined: 09 Sep 2013
Posts: 32811
Own Kudos [?]: 827 [0]
Given Kudos: 0
Send PM
Re: If P and Q are positive integers, is the product 3P^Q divisible by 2? [#permalink]
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
Re: If P and Q are positive integers, is the product 3P^Q divisible by 2? [#permalink]
Moderator:
Math Expert
93072 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne