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:

Re: IR question from Princeton Review 2013.. help needed [#permalink]

Show Tags

09 Jun 2012, 22:03

5

This post received KUDOS

Here are my notes. How did I do? Helpful?

Section 1:

A: No. Only implies that it's happened before, possibly last year.

B: Yes. Midwest Mean = West Mean = min(all means).

C: No. Could be Level 2 + anybody else, probably also ROMs.

D: Yes. He/she can delegate.

Section 2:

A: We know that BB is 50% of difference between ticket price and that region's mean. For West, mean is 200. Only tickets purchases below 1 SD (25) are the 18 purchased at 150. A few different ways to do the math here, I'll do this: 200 - 150 = 50 50 * 50% = 25 25 * 18 = (25*20) - (25*2) = 500 - 50 = 450 :. West will receive BB of $450. :. True

B: Mid-Atlantic info from chart: 500 sample size, 350 mean, and SD of 50. I'm not convinced about this one because I'm not sure whether this is a normal distribution. In a SD, 68% of the tickets would be within one standard deviation and 95% of the tickets would be within two. Let's run with that. So $450 is two standard deviations away, so is 5% / 2 of the sample size greater than 20? It's important that we also divide 5% by 2 because that's just the portion that is on the upper end of the normal distribution. 500 * 0.1 = 50 * 0.1 = 5 :. 5 = 1% of 500 :. 5% of 500 = 25 :. 2.5% = 12.5 :. 12.5 < 20 :. False

C: Same process as in B. 400 sample size, 300 mean, and 50 SD. This time we're only talking about one SD though. Is 32% / 2 of the sample size greater than 50? Let's estimate because it's timed. 400 * .1 = 40 * 3 = 120 = 30% of 400 :. 15% of 400 = 60 :. 60>50 :. True

Re: IR question from Princeton Review 2013.. help needed [#permalink]

Show Tags

14 Jun 2012, 19:27

It is worth noting that statistics have been defined as "normally distributed" That's why , 68% will fall under 1 Deviation (32% lie outside) 95% will fall under 2 Deviation 99.5% will fall under 3 Deviation 99.999997% will fall under 6 deviation Had it not been the "normal distribution", answer of C (II question) might have been different.
_________________

Re: IR question from Princeton Review 2013.. help needed [#permalink]

Show Tags

30 Dec 2015, 07:39

Hello,

Can someone help me explain how the precentage of the normal deviation is determined? I am not familiar on how you receive the % of 2 and 16 % for the sections B and C under Section 2.

Re: IR question from Princeton Review 2013.. help needed [#permalink]

Show Tags

27 Feb 2016, 20:23

mdellaratta wrote:

Hello,

Can someone help me explain how the precentage of the normal deviation is determined? I am not familiar on how you receive the % of 2 and 16 % for the sections B and C under Section 2.

Still too new to post the link, so unable to share the pic here. Anyway, just google "34 14 2 standard deviation" and the answer is in GRE SparkNotes. I also learned this new piece info from the same question.

gmatclubot

Re: IR question from Princeton Review 2013.. help needed
[#permalink]
27 Feb 2016, 20:23