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Recently Mary gave a birthday party for her daughter at [#permalink]
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13 Sep 2008, 02:53
Question Stats:
48% (01:27) correct 52% (01:42) wrong based on 647 sessions
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Recently Mary gave a birthday party for her daughter at which she served both chocolate and strawberry ice cream. There were 8 boys who had chocolate ice cream, and nine girls who had strawberry. Everybody there had some ice cream, but nobody tried both. What is the maximum possible number of girls who had some chocolate ice cream? (1) Exactly thirty children attended the party. (2) Fewer than half the children had strawberry ice cream.
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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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22 Jan 2015, 12:55
Hi All, I imagine that many Test Takers would misinterpret the information in the prompt.....UNTIL they read the information in Fact 1, then they'd catch the error. To start, we're given some information on SOME of the children who attended a party: 1) There were 8 boys who had chocolate ice cream 2) There were 9 girls who had strawberry ice cream 3) NOBODY had both flavors of ice cream 4) EVERYBODY had ice cream. The misinterpretation is that there were only 17 children at the party. The prompt does NOT state that, so we have to keep an open mind to the idea that there were MORE children and that we don't know what type of ice cream THOSE children ate. The specific question asks for the MAXIMUM POSSIBLE number of girls who had chocolate ice cream, so THAT also implies that there were additional children beyond the 17 described. Fact 1: 30 children attended the party. Here we have an actual number to work with. 30 total children  the 17 mentioned in the prompt = 13 additional children. We don't know if they're boys or girls and we don't know whether they ate chocolate or strawberry ice cream. All of that is fine  the question is asking for the maximum POSSIBLE number of girls who COULD have had chocolate ice cream. IF those 13 extra children were ALL girls and IF they ALL had chocolate ice cream.....then that would make the maximum possible = 13. Fact 1 is SUFFICIENT. Fact 2: Fewer than half the children had strawberry ice cream. Since we know that 9 had strawberry and 8 had chocolate, this Fact also implies that there were additional children. Unfortunately, we don't know how many. There would have to be AT LEAST 2 extra children, but it could be dozens or hundreds and we have no idea about whether they're male or female or what type of ice cream each ate. Fact 2 is INSUFFICIENT. Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: Zumit DS 025 [#permalink]
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14 Sep 2008, 00:37
dancinggeometry wrote: Recently Mary gave a birthday party for her daughter at which she served both chocolate and strawberry ice cream. There were 8 boys who had chocolate ice cream, and nine girls who had strawberry. Everybody there had some ice cream, but nobody tried both. What is the maximum possible number of girls who had some chocolate ice cream?
(1) Exactly thirty children attended the party. (2) Fewer than half the children had strawberry ice cream. 1)is INSUFFI no info about the number of icecreams !!! 2)does not say about total number of children !!! (1) and (2) => say g_c=girls having choc ice cream and boys b_s boys having strawber icecream then g_c+b_s +17=30 => g_c+b_s=13 => when b_s=0 then g_c = max = 13 IMO C
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Re: Mary  party [#permalink]
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19 Nov 2009, 13:17
kairoshan wrote: Recently Mary gave a birthday party for her daughter at which she served both chocolate and strawberry ice cream. There were 8 boys who had chocolate ice cream, and nine girls who had strawberry. Everybody there had some ice cream, but nobody tried both. What is the maximum possible number of girls who had some chocolate ice cream?
(1) Exactly thirty children attended the party.
(2) Fewer than half the children had strawberry ice cream. This doesn't make any logical sense as a DS question  a DS question cannot ask for the 'maximum number' of something, since it is impossible to know what kind of information would be sufficient to answer such a question. Simplifying matters, if I ask, for example, What is the maximum possible number of stamps in Bill's collection? 1) Bill has fewer than 30 stamps in his collection. 2) Bill has an even number of stamps in his collection. From Statement 1, we know the maximum possible is 29, but from Statements 1+2 together we know the maximum is 28. So is Statement 1 sufficient alone? Or do we need both? Or is the answer E? The question doesn't have a unique correct answer, and is completely illogical  you could never see such a question on the real GMAT. The same is true of the question in the original post above. I'd be curious to know the source of the original question, but it's best ignored.
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Re: Zumit DS 025 [#permalink]
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14 Jun 2011, 15:54
Yeh the Question is strange, however i found this today in MGMAT test. And naturally didnt do it right, so thought to check what other people think of such question. Answer could be explained as follows, however i am not still very convinced or i should say that it is just a 'hidden trap' of gmat. Attachment:
cs.JPG [ 5.58 KiB  Viewed 8878 times ]
From statement 1 Total = 30 kids. to maximize, girls eating choclate icecream, boys eating strawberry could be assumed!! to be 0, since it is not stated that there must be atleast one boy who eats strawberry icecream. so the max girls eating choclate icecream will be  3089 = 13 girls. st2 doesnt provide info on boys choclate icecream.  the trap is that one may not assume that boys eating strawberry icecream could be 0, and think that st1 may not be sufficient. so in that case both statements would be required. but the idea is to read the word 'maximum' in the Question.



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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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18 Apr 2014, 06:00
What should be done in such a case?. Is the answer  A , C or E? Any Expert Opinion?
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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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18 Apr 2014, 11:20



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Recently Mary gave a birthday party for her daughter at [#permalink]
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20 Jul 2014, 02:28
This is how I think A is sufficient Out of 30 children, to get the maximum value of girls eating chocolate icecream, we should choose minimum # of boys to eat strawberry icecream... (to be fair to the boys, I chose 1 strawberry icecream for them and got 12 girls eat chocolate icecream )... (refer to the matrix picture posted by agdimple333) let me know if my approach is incorrect.



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Recently Mary gave a birthday party for her daughter at [#permalink]
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26 Jul 2014, 07:43
1) Total children = 30 Let total girls be x. Therefore total boys = 30x Now to get the max of GirlsChocolatte (a) we have to maximize x. To maximize x , BoysStrawberry has to be zero. Then 30x=8 X=22 Now a+9=22 A=13 Thus statement 1 sufficient. 2) Insufficient : Since total is not known hence insufficient.
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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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31 Aug 2014, 04:41
1) As we have 30 children and we know that 8 boys had chocolate and 9 girls had strawberry, we are left with 3017=13. These 13 can be considered girls who had chocolate. Question is asking maximum possible girls who had chocolate thus we can assume these 13 as girls who had choco ice cream. No need to calculate anything.
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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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23 Dec 2014, 05:05
as we need maximum number of girls having chocolate ice cream then we are given 8 boys with chocolate ice cream so for maximum girls we have limit the number of boys to minimum that is out to 30 children rest 13 must be girls. Hence option A. hope this one helps.



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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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22 Jan 2015, 09:44
Please forgive me if I am being dumb, if nobody tried both strawberry and chocolate, how are we going to have people who tried both of them??



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Re: Recently Mary gave a birthday party for her daughter at [#permalink]
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23 Jan 2015, 00:02
Tmoni26 wrote: Please forgive me if I am being dumb, if nobody tried both strawberry and chocolate, how are we going to have people who tried both of them?? We don't have any people who tried both and no solution has considered both. As for the solution to this question, the question is not correct. It is a DS question  you need to find out whether the given data is sufficient to answer the question. So it is illogical to ask for a maximum or minimum value. The maximum or minimum values change with information. The more relevant information you provide, the more restricted the range becomes and hence the maximum changes.
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Recently Mary gave a birthday party for her daughter at [#permalink]
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18 Feb 2015, 16:14
This question is asked in a tricky way..the key is in the wording.. it says what is the max POSSIBLE (not necessarily actual) and since no kid had both kind of ice cream you can assume that the rest of the children are girl there for you only need to know the total so
(A) is sufficient. (B) alone does not tell you anything about "how many" in term of concrete number
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