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.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

For any integer in the set,where 3 is a member of the set,the sum of 3 and that integer is in p.

lets say the number in the set is 5. then statement 1 says 5 and 8 are in the set.Why do we assume that all the members in the set r multiples of 3 like '3'.its given that 3 is a member of the set.it doesnt say that all the numbers in the set are multiples of 3.

(1) For any integer in P, the sum of 3 and that integer is also in P:

It is already given in the question stem that 3 is in the set P. So this statement sets the trigger. That means 3, 6, 9, ...... infinite will be part of the set P. So the answer to the question "is every positive multiple
of 3 in P" is affirmative. SUFFICIENT

(2) For any integer in P, that integer minus 3 is also in P.

It is already given in the question stem that 3 is in the set P. So this statement sets the trigger. That menas 0, -3, -6, -9.... ....infinite will be in set P. So the answer to the question is negative. SUFFICIENT.

But why assume that 3 is the only member in the set?

thats my prob.

sudzpwc,

We are not assuming that 3 is the only member in the set P. There could be other integers in the set P. But in the question stem (not in the statements), it is given that 3 is the part of P. So you have to accept that 3 is member of P and then consider each statment.

The question asked "Are all positive multiples of 3 in P?". With statement (II) 3, 0, -3, -6 ..... i.e. every positive multiple of 3 isn't in P.Hence the statement is sufficient.
IMO, D is the correct choice.

The question asked "Are all positive multiples of 3 in P?". With statement (II) 3, 0, -3, -6 ..... i.e. every positive multiple of 3 isn't in P.Hence the statement is sufficient. IMO, D is the correct choice.

This is tricky. Here you have unknowingly assumed that 3 is the starting point. Now for the time being imagin that set P contains infinite integers in such a way that it fulfills the condition of statement II. For example start from 999. Then 999, 996, 993......3, 0, -3, -6,.....
all are in set P. Here I have used 999 as a starting point just to as an example. It could be an infinite number. IN that the answer to the question would be YES.

So the stament II can result in YES as well as NO. NOT SUFF.

The question asked "Are all positive multiples of 3 in P?". With statement (II) 3, 0, -3, -6 ..... i.e. every positive multiple of 3 isn't in P.Hence the statement is sufficient. IMO, D is the correct choice.

No. You only know what MUST be in, but not what actually is. Suppose P is the set of ALL integers? Then every positive multiple of 3 IS in P.
_________________

Best,

AkamaiBrah Former Senior Instructor, Manhattan GMAT and VeritasPrep Vice President, Midtown NYC Investment Bank, Structured Finance IT MFE, Haas School of Business, UC Berkeley, Class of 2005 MBA, Anderson School of Management, UCLA, Class of 1993

If P is a set of integers and 3 is in P, is every positive multiple
of 3 in P?

(1) For any integer in P, the sum of 3 and that integer is also in P. 3 is in, so 6, 9, 12, ... so on are in as well --- SUFF

(2) For any integer in P, that integer minus 3 is also in P. 3 is in, so 0, -3, -6, -9, ... so on are in as well --- can we say something different about POSITIVE multiples? They can be in P, and they can be not.