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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

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:

The only way for (3x + 1)/10 to have a remainder of 0 would be if 3x has a units digit of 9, so that when you add 1 to it you get a mulitple of 10. So x=3, 13, 23, etc would do it.

Statement 2 is obviously not sufficient by itself, as x would work for 13, but not for say 10 for example.

Statement 1 gives a way to determine x. If you try n=1 it doesn't work and you have x>4. So you know that statement 2 doesn't add any value and your answer must be A or E. Now you have to try and see if there is a case where it would work. If you can find a case where it does work using statement 1 then your answer is E, if you can't find a case where it works then your answer is A, as statement 1 would tell you that (3x+1)/10 does not have a remainder of 0.

In order for it to work you need x to have a units digit of 3. So 3n+2 must have a units digit of 3. Because you are adding 2 you need 3n to have a units digit of 1. This occurs when x=7 because 7*3=21.