• Magoosh
Study with Magoosh GMAT prep

Available with Beat the GMAT members only code

• Free Trial & Practice Exam
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• 1 Hour Free
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• Free Veritas GMAT Class
Experience Lesson 1 Live Free

Available with Beat the GMAT members only code

• Reach higher with Artificial Intelligence. Guaranteed
Now free for 30 days

Available with Beat the GMAT members only code

• 5-Day Free Trial
5-day free, full-access trial TTP Quant

Available with Beat the GMAT members only code

• Get 300+ Practice Questions
25 Video lessons and 6 Webinars for FREE

Available with Beat the GMAT members only code

• 5 Day FREE Trial
Study Smarter, Not Harder

Available with Beat the GMAT members only code

• Award-winning private GMAT tutoring
Register now and save up to $200 Available with Beat the GMAT members only code • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code ## Can someone please give me the reasoning to this DS problem? This topic has 1 expert reply and 3 member replies daygoballa Junior | Next Rank: 30 Posts Joined 26 Feb 2009 Posted: 10 messages Test Date: June 2009 Target GMAT Score: 730 #### Can someone please give me the reasoning to this DS problem? Thu Mar 05, 2009 2:42 pm Here's the problem: - Of the 66 people in a certain auditorium, at most 6 people have birthdays in any one given month. Does at least one person in the auditorium have a birthday in January? (1) More of the people in the auditorium have birthdays in February than in March. (2) five of the people in the auditorium have birthdays in March. The answer is (D) Thank you for you help! Henry ### GMAT/MBA Expert Rich.C@EMPOWERgmat.com Elite Legendary Member Joined 23 Jun 2013 Posted: 9309 messages Followed by: 478 members Upvotes: 2867 GMAT Score: 800 Mon Feb 19, 2018 9:11 pm Hi All, We're told that there are 66 people in a certain auditorium and 6 people AT MOST have birthdays in any one given month. We're asked if AT LEAST one person in the auditorium has a birthday in January. This is a YES/NO question and we can use a mix of logic and TESTing VALUES to answer it. To start, since there are 66 people, no more than 6 have their birthdays in the same month and there are 12 months in a year, the ONLY WAY for one month to have 0 birthdays is if ALL of the other 11 months have 6 birthdays each. In that situation, there would be eleven 6s and one 0. By extension, if ANY month doesn't have 6 birthdays in it, then EVERY month would have at least one birthday in it. 1) More of the people in the auditorium have birthdays in February than in March. Fact 1 tells us that March cannot possibly have 6 birthdays (it would have at most 5 - and that could only occur if February had 6 birthdays). Thus, since one month (in this case, March) doesn't have 6 birthdays, January will have at least 1 birthday. Fact 1 is SUFFICIENT 2) Five of the people in the auditorium have birthdays in March. The information in Fact 2 allows us to make the same deduction that we made in Fact 1: since one month (in this case, March) doesn't have 6 birthdays, January will have at least 1 birthday. Fact 2 is SUFFICIENT Final Answer: D GMAT assassins aren't born, they're made, Rich _________________ Contact Rich at Rich.C@empowergmat.com TedCornell Master | Next Rank: 500 Posts Joined 09 Mar 2009 Posted: 207 messages Followed by: 22 members Upvotes: 115 Test Date: March 9 2009 GMAT Score: 750 Wed Mar 25, 2009 12:26 am On the GMAT, when you're told that 5 of the ppl have birth day in march that means exactly 5 of those people. There could be others with march birthdays, but those others cannot be among the people in the auditorium. Similarly, if you're told "John has$10" it means he has exactly $10; he cannot have$11 or \$12.

To make 6 march birthdays a possibility, the statement might've said "At least 5 of the pple have birthday in march" or "no fewer than 5 of the ppl"

cramya Legendary Member
Joined
28 Aug 2008
Posted:
2469 messages
Followed by:
11 members
Upvotes:
331
Thu Mar 05, 2009 2:54 pm
Take the easier of the 2 statements

Stmt II

5 bday in March

Remaining 61
and 11 months includinbg Jan left

Atmost 6 can have a bday in any given month so there must be atleast 1 if not more having bday in Mar

SUFF

Stmt II

More of the people in the auditorium have birthdays in February than in March

Again to prove no one has a bday in jan try to maximize the 10 months which is 60 excluding March and Jan.

Since March cant have 6 as it should be less than Feb at the max March can be 5.

Still jan we have 1 bday.

SUFF

Choose D

ranpman Newbie | Next Rank: 10 Posts
Joined
01 Mar 2009
Posted:
1 messages
Mon Mar 23, 2009 5:58 pm
cramya wrote:
Take the easier of the 2 statements

Stmt II

5 bday in March

Remaining 61
and 11 months includinbg Jan left

Atmost 6 can have a bday in any given month so there must be atleast 1 if not more having bday in Mar

SUFF

Stmt II

More of the people in the auditorium have birthdays in February than in March

Again to prove no one has a bday in jan try to maximize the 10 months which is 60 excluding March and Jan.

Since March cant have 6 as it should be less than Feb at the max March can be 5.

Still jan we have 1 bday.

SUFF

Choose D
I agree that (1) is SUFFICIENT.

However (2) states that "Five of the people in the auditorium have birthdays in March". (2) does not hay "ONLY five of the people in the auditorium have...".

In that case, isn't it possible that March could have 6 birthdays? In which case, (2) is INSUFFICIENT. What am I missing?

### Best Conversation Starters

1 lheiannie07 80 topics
2 LUANDATO 59 topics
3 ardz24 52 topics
4 AAPL 45 topics
5 Roland2rule 43 topics
See More Top Beat The GMAT Members...

### Most Active Experts

1 Rich.C@EMPOWERgma...

EMPOWERgmat

133 posts
2 Brent@GMATPrepNow

GMAT Prep Now Teacher

131 posts
3 GMATGuruNY

The Princeton Review Teacher

130 posts
4 Scott@TargetTestPrep

Target Test Prep

118 posts
5 Jeff@TargetTestPrep

Target Test Prep

114 posts
See More Top Beat The GMAT Experts