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:

Re: is it an integer? [#permalink]
06 Aug 2009, 21:59

1

This post received KUDOS

A

Statement 1: if u take N=5 and any value for M it will always hold true that is (10^M + N)/3 an integer; becoz 10^M ( let M = any value) will always leave a reminder of 1....and 1+5 = 6 which is divisable by 3 ....sufficient

Statement 2 : if MN is even ...this means (M,N) can be both even or odd (except both being odd at a time)....if taken an example....

Re: is it an integer? [#permalink]
06 Aug 2009, 22:13

1

This post received KUDOS

Expert's post

Let's consider 10^M

at M>=0: 10^M = {1, 10, 100, 1000....} or 3k+1 at M<0: 10^M is a fraction and our expression is not an integer.

Now, let's see our statements:

1) N=5 at M>=0: (3k+1 + 5) /3 = k+2 - an integer at M<0: a fraction. insufficient

2) MN is even a) at M=2, N=5 our expression is an integer b) at M=-2, N=-5 our expression in a fraction insufficient

1)&2) N=5 & MN is even --> N=5, M is even For all even M>=0 we will get an integer. Now we have interesting question: Could negative numbers be even or odd? if yes, we can choose M=-2, N=5 and get a fraction. if no, M cannot be negative and two statements are sufficient.

Hey everyone, today’s post focuses on the interview process. As I get ready for interviews at Kellogg and Tuck (and TheEngineerMBA ramps up for his HBS... ...