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:

Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a [#permalink]

Show Tags

07 Sep 2016, 08:32

1

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

45% (medium)

Question Stats:

62% (01:13) correct 38% (01:23) wrong based on 55 sessions

HideShow timer Statistics

Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a photo. What is the probability that none of the three girls will stand next to one another?

Re: Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a [#permalink]

Show Tags

07 Sep 2016, 09:26

1

This post received KUDOS

DrAB wrote:

Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a photo. What is the probability that none of the three girls will stand next to one another?

(A) 0,1 (B) 0,2 (C) 0,3 (D) 0,4 (E) 0,5

Out of 5 , then the only position the three girls can take are 1, 3 and 5th so they are have 3! ways of standing in those position and remaining 2 boys can have 2! ways. So Probability = \(\frac{3! * 2!}{5!} =\frac{1}{10}\) Answer is A

Re: Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a [#permalink]

Show Tags

07 Sep 2016, 17:39

Senthil1981 wrote:

DrAB wrote:

Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a photo. What is the probability that none of the three girls will stand next to one another?

(A) 0,1 (B) 0,2 (C) 0,3 (D) 0,4 (E) 0,5

Out of 5 , then the only position the three girls can take are 1, 3 and 5th so they are have 3! ways of standing in those position and remaining 2 boys can have 2! ways. So Probability = \(\frac{3! * 2!}{5!} =\frac{1}{10}\) Answer is A

This is a poor-quality question. How can one tell there are 3 girls?

Re: Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a [#permalink]

Show Tags

07 Sep 2016, 19:19

I did it this way...

BTW we can tell the number of girls (although I though this should be more clear) because, based on the answer choices, we know there is at least ONE way they can stand all separate. So there are 3 girls and 2 boys.

Re: Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a [#permalink]

Show Tags

07 Sep 2016, 19:42

1

This post received KUDOS

Donnie84 wrote:

Senthil1981 wrote:

DrAB wrote:

Five people, Ada, Ben, Cathy, Dan, and Eliza, are lining up for a photo. What is the probability that none of the three girls will stand next to one another?

(A) 0,1 (B) 0,2 (C) 0,3 (D) 0,4 (E) 0,5

Out of 5 , then the only position the three girls can take are 1, 3 and 5th so they are have 3! ways of standing in those position and remaining 2 boys can have 2! ways. So Probability = \(\frac{3! * 2!}{5!} =\frac{1}{10}\) Answer is A

This is a poor-quality question. How can one tell there are 3 girls?

The question says "none of the three girls". Could this mean differently ?

We're given 3 girls and 2 boys and told to put them in a line. We're asked for the probability that none of the three girls will stand next to one another. This question can be approached in a number of different ways. Here's how you can use permutations and probability to get to the correct answer:

With 5 people, there are 5! = 120 possible arrangements. Lining up the 5 people, there's just one option for the 3 girls to NOT stand next to one another:

GBGBG = (3)(2)(2)(1)(1) = 12 options

Thus, the probability of the 3 girls NOT standing next to one another is 12/120 = 1/10 = 10% = .1