GMAT Prep Q - P&C

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GMAT Prep Q - P&C

by tito1545 » Sun Feb 20, 2011 10:13 am
A step by step approach for this please :

A certain office supply store stocks 2 sizes of self-stick notepads,each in 4 colours:blue,green,yellow,pink.The store packs the notepads in packages that contain either 3 notepads of the same size and the same colour or 3 notepads of the same size and of 3 different colours.If the order in which the colours 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

ANS C
Source: — Problem Solving |

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by Night reader » Sun Feb 20, 2011 10:26 am
more about logic: 3 notepads of the same size and the same color 4C1 *3=12 AND 3 notepads of the same size and of 3 different colors --> 4C3 *3=12. But the question inquires about how many different packages of the types described above are possible ? so from 4C1 *3=12 we keep only four packages with different colors - hence different self-stick, as no difference between the self-sticks exists
solution: 4C3 *3 + 4= 16

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tito1545 wrote:A step by step approach for this please :

A certain office supply store stocks 2 sizes of self-stick notepads,each in 4 colours:blue,green,yellow,pink.The store packs the notepads in packages that contain either 3 notepads of the same size and the same colour or 3 notepads of the same size and of 3 different colours.If the order in which the colours 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

ANS C
My knowledge frontiers came to evolve the GMATPill's methods - the credited study means to boost the Verbal competence. I really like their videos, especially for RC, CR and SC. You do check their study methods at https://www.gmatpill.com

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by tito1545 » Sun Feb 20, 2011 11:47 am
Thanks a ton for this.

One query here , could you please elaborate on the second part on how you got 16 ???

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by Night reader » Sun Feb 20, 2011 1:14 pm
just copy/paste for your attention --> the question inquires about how many different packages of the types described above are possible ? so from 4C1 *3=12 we keep only four packages with different colors - hence different self-stick, as no difference between the self-sticks exists; solution: 4C3 *3 + 4= 16
tito1545 wrote:Thanks a ton for this.

One query here , could you please elaborate on the second part on how you got 16 ???
My knowledge frontiers came to evolve the GMATPill's methods - the credited study means to boost the Verbal competence. I really like their videos, especially for RC, CR and SC. You do check their study methods at https://www.gmatpill.com

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Posts: 27
Joined: Sat Feb 27, 2010 12:05 pm
Location: England

by tito1545 » Sun Feb 20, 2011 2:16 pm
got it m8 thanks a ton !