Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 25 May 2017, 07:40

### GMAT Club Daily Prep

#### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Combinatorics (very difficult)

Author Message
Manager
Joined: 22 Jun 2008
Posts: 102
Schools: Darden School of Business (Class of 2012)
Followers: 1

Kudos [?]: 34 [0], given: 1

### Show Tags

08 Sep 2008, 09:39
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Hi guys, I made a gmat prep yesterday and score more than 700. I need help with the following problem:

"A certain office supply store stocks 2 sizes of self stick notepads, each in 4 colors, blue, green, yelow or pink. The store packs the notepad in packages that contain either 3 notepads of the same size and of the same color or 3 notepads of the same size and of 3 different colors. If the order in which the colors are packed is not considered, how many different packages of the types described above are possible?"

A) 6 B) 8 C) 16 D) 24 E)32
SVP
Joined: 07 Nov 2007
Posts: 1806
Location: New York
Followers: 38

Kudos [?]: 931 [1] , given: 5

### Show Tags

08 Sep 2008, 09:46
1
KUDOS
lordw wrote:
Hi guys, I made a gmat prep yesterday and score more than 700. I need help with the following problem:

"A certain office supply store stocks 2 sizes of self stick notepads, each in 4 colors, blue, green, yelow or pink. The store packs the notepad in packages that contain either 3 notepads of the same size and of the same color or 3 notepads of the same size and of 3 different colors. If the order in which the colors are packed is not considered, how many different packages of the types described above are possible?"

A) 6 B) 8 C) 16 D) 24 E)32

B G Y P -- Size 1
b g y p -- Size 2

For Size -1:
No . of ways 3 notepads of the same size and of the same color = 4 (BBB,GGG, YYY, PPP)
No . of ways 3 notepads of the same size and of 3 different colors= 4C3 (BGY,PGY, YPB, BPG)

For size -1 = 4+4C3 = 8
similarly For size -2 = 4+4C3 = 8

Total =16
_________________

Smiling wins more friends than frowning

Intern
Joined: 27 Aug 2007
Posts: 34
Followers: 1

Kudos [?]: 17 [1] , given: 0

### Show Tags

08 Sep 2008, 09:48
1
KUDOS
3 notepads of the same size and of the same color
4(colors) * 2 (sizes) = 8

3 notepads of the same size and of 3 different colors
4C3 (colors) * 2 (sizes) = 8

Total = 16 (C).

OA?
Director
Joined: 12 Jul 2008
Posts: 518
Schools: Wharton
Followers: 22

Kudos [?]: 155 [0], given: 0

### Show Tags

08 Sep 2008, 10:28
lordw wrote:
Hi guys, I made a gmat prep yesterday and score more than 700. I need help with the following problem:

"A certain office supply store stocks 2 sizes of self stick notepads, each in 4 colors, blue, green, yelow or pink. The store packs the notepad in packages that contain either 3 notepads of the same size and of the same color or 3 notepads of the same size and of 3 different colors. If the order in which the colors are packed is not considered, how many different packages of the types described above are possible?"

A) 6 B) 8 C) 16 D) 24 E)32

Same size and same color = 2*4 = 8
Same size and 3 different colors = 2*(4C3) = 8
Total = 8 + 8 = 16
Manager
Joined: 22 Jun 2008
Posts: 102
Schools: Darden School of Business (Class of 2012)
Followers: 1

Kudos [?]: 34 [0], given: 1

### Show Tags

08 Sep 2008, 11:46

lkothari wrote:
3 notepads of the same size and of the same color
4(colors) * 2 (sizes) = 8

3 notepads of the same size and of 3 different colors
4C3 (colors) * 2 (sizes) = 8

Total = 16 (C).

OA?
Re: Combinatorics (very difficult)   [#permalink] 08 Sep 2008, 11:46
Display posts from previous: Sort by