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 350,000 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:

If ten students appear in an examination and 4 of them are [#permalink]
06 Jan 2004, 15:14

If ten students appear in an examination and 4 of them are appearing for mathematics and rest for 6 different subjects, in how many ways can they be seated in a row so that no copying is possible?

If ten students appear in an examination and 4 of them are appearing for mathematics and rest for 6 different subjects, in how many ways can they be seated in a row so that no copying is possible?

If it were a computer adaptive test then it would be 10!

If ten students appear in an examination and 4 of them are appearing for mathematics and rest for 6 different subjects, in how many ways can they be seated in a row so that no copying is possible?

I'm a little confused now, there are only 5 spaces between 6 students. I'm not in my right mind today - stressful day in the markets for me.

If ten students appear in an examination and 4 of them are appearing for mathematics and rest for 6 different subjects, in how many ways can they be seated in a row so that no copying is possible?

I'm a little confused now, there are only 5 spaces between 6 students. I'm not in my right mind today - stressful day in the markets for me.

subtract number of ways in which atleast two are together from the total number of ways.

if 2 are together then we have 4C2 and treating this as one group we have 8 people left so number of ways = 4C2 * (8+1)!
smilarly 3 people together = 4C3 * (7+1)!
and 4 people together = 4C4 * (6+1)!

total ways in which copying takes place =
4C2 * 9! + 4C3 * 8! + 4C4 * 7! = 7! * 465
subtract this from 10!
so we get
7! ( 10*9*8 - 465 ) = 255 * 7!

Hello everyone! Researching, networking, and understanding the “feel” for a school are all part of the essential journey to a top MBA. Wouldn’t it be great... ...

Booth allows you flexibility to communicate in whatever way you see fit. That means you can write yet another boring admissions essay or get creative and submit a poem...