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Senior | Next Rank: 100 Posts
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by rainbownlife » Mon Feb 04, 2008 3:26 pm
Division A of company X has 4850 customers.If there were 86 service errors in division A, what was the service-error rate , in number of service error per 100 customers, for division B of company X?
(1) overall service error rate for Div A dn B combined is 1.5 service errors per 100 customers.
(2) Div B has 9350 customers, none of who were customers of div a.

Why is (1) not sufficient?
Correct answer is : Both (1) and (2) together are sufficient.
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Source: — Data Sufficiency |
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by cris » Tue Feb 05, 2008 4:44 am
stm.1 would be SUFF if we knew that "none of the customers of div b were customers of div a"....but that info we get it in stm. 2

What is important of stm. 2) is that piece of info...no the total customers of div b. I think that if stm. 2 only said that none of the customers of div. b are customers of div. a C would s till be the answer.

Correct me if I am wrong.
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by rainbownlife » Tue Feb 05, 2008 11:21 am
thanks for your response.

If this were a PS problem instead how would we go about solving it?
I guess i am just trying to nderstand what information is required to solve such a problem.
thanks so much !
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by gmatguy16 » Tue Feb 05, 2008 7:31 pm
cris,can you please explain how stm.1 would be SUFF if we knew that "none of the customers of div b were customers of div a..
say Y is # of customers and y is # of service errors for division b from statement 1 we know ,(y+86)/(Y+4850)=0.15 so y/Y is unknown.
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