DS - manufacturer conducted a survey

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DS - manufacturer conducted a survey

by Xbond » Wed Aug 26, 2009 10:02 am
Hi there,

Could you explain in the simplest this concept and how to resolve it


A manufacturer conducted a survey to determine how many people buy products P and Q.
What fraction of the people surveyed said that they buy neither product P nor product Q ?

(1) 1/3 of the people surveyed said that they buy product P but not product Q
(2) 1/2 of the people surveyed said that they buy product Q
Source: — Data Sufficiency |

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Re:

by rahulmehra13 » Wed Aug 26, 2009 11:50 am
Check the attachment.
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answer.docx
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by m&m » Wed Aug 26, 2009 12:25 pm
you can easily see this by drawing ven diagrams, but I'll try to explain it in words.

You have 4 options
- buy p and not q
- buy p and buy q
- not p and buy q
- not p and not q

knowing any 3 will allow you to solve the 4th

so... (1) says p and not q --> insuff

(2) says buy q -- so that constitutes buy p and not q and buy p and buy q --> still insuff

(combined) we have 3 of the above options so we can solve for unknown

... you don't need to ACTUALLY solve, just need to know that you COULD solve to show sufficiency

hope that helps

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Xbond wrote:Hi there,

Could you explain in the simplest this concept and how to resolve it


A manufacturer conducted a survey to determine how many people buy products P and Q.
What fraction of the people surveyed said that they buy neither product P nor product Q ?

(1) 1/3 of the people surveyed said that they buy product P but not product Q
(2) 1/2 of the people surveyed said that they buy product Q
Rephrase :

P + Q - Both + Neither = 100

1. Gives (P - Both) info - No info about Q. insufficient
2. Gives Q info - No info of P & Both. Not sufficient

1&2 -> We have (P-B) & Q, we can find Neither.

HTH.