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George has a total of B books in his library, 25 of which are hardcove
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16 Jun 2016, 02:47
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George has a total of B books in his library, 25 of which are hardcover fiction books. What is the value of B? (1) 40 of the B books are fiction and the rest are nonfiction (2) 60 of the B books are hardcovers and the rest are paperbacks
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Re: George has a total of B books in his library, 25 of which are hardcove
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16 Jun 2016, 11:22
Bunuel wrote: George has a total of B books in his library, 25 of which are hardcover fiction books. What is the value of B?
(1) 40 of the B books are fiction and the rest are nonfiction (2) 60 of the B books are hardcovers and the rest are paperbacks Statement 1: Total fiction books= 40 Hardcover fiction books= 25 So, papercover fiction books= 15 (4025) Since the total books is B and and fiction books are 40. Non fiction would be (B40) We don't know the value of nonfiction books (both hard cover and paper cover) Not sufficient. Statement 2 Hardcover books= 60 Fiction and Hardcover books= 25 So, non fiction hardcover books are= 35 (6035) Just as in statement 1, this statement does not give us the number of papercover book (both fiction and non fiction) Not sufficient. Combining both statements, we do not get the answer as we do not know the number of nonfiction and papercover books. E is the answer
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Re: George has a total of B books in his library, 25 of which are hardcove
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16 Jun 2016, 05:19
Is this E by any chance as we dont have sufficient info about Non fiction books



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Re: George has a total of B books in his library, 25 of which are hardcove
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16 Jun 2016, 08:02
it took be bloody 6 minutes to solve this question
IMO C, sorry dificult to write explaination..... waiting for OA



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Re: George has a total of B books in his library, 25 of which are hardcove
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16 Jun 2016, 08:17
E for me too.
no info about NonFiction Paper back



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Re: George has a total of B books in his library, 25 of which are hardcove
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16 Jun 2016, 08:40
Bunuel wrote: George has a total of B books in his library, 25 of which are hardcover fiction books. What is the value of B?
(1) 40 of the B books are fiction and the rest are nonfiction (2) 60 of the B books are hardcovers and the rest are paperbacks Stem FI  NF   25  ??  HC  ??  ??  PB  1) FI  NF   25  ??  HC  15  ??  PB  ^  Total = 40 Insufficient2) FI  NF   25  35  HC <= Total = 60  ??  ??  PB  InsufficientBoth FI  NF   25  35  HC  15  ??  PB  InsufficientE is the answer.



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Re: George has a total of B books in his library, 25 of which are hardcove
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18 Jun 2016, 03:52
IMO E info given f  Nf total HC25 PB  A) f  Nf total HC25 PB14 T 40 Clearly not sufficient B) f  Nf total HC253560 PB T  Insufficient A and B combined f  Nf total HC253560 PB15?? T 40?? Still value of nonfiction paper back is not known there not sufficient So E
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Re: George has a total of B books in his library, 25 of which are hardcove
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18 Jun 2016, 06:26
Divyadisha wrote: Bunuel wrote: George has a total of B books in his library, 25 of which are hardcover fiction books. What is the value of B?
(1) 40 of the B books are fiction and the rest are nonfiction (2) 60 of the B books are hardcovers and the rest are paperbacks Statement 1: Total fiction books= 40 Hardcover fiction books= 25 So, papercover fiction books= 15 (4025) Since the total books is B and and fiction books are 40. Non fiction would be (B40) We don't know the value of nonfiction books (both hard cover and paper cover) Not sufficient. Statement 2 Hardcover books= 60 Fiction and Hardcover books= 25 So, non fiction hardcover books are= 35 (6035) Just as in statement 1, this statement does not give us the number of papercover book (both fiction and non fiction) Not sufficient. Combining both statements, we do not get the answer as we do not know the number of nonfiction and papercover books. E is the answer I think you meant (6025), not (6035)
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Re: George has a total of B books in his library, 25 of which are hardcove
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03 Jul 2016, 23:46
IMO A...
What is the OA and OE?



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Re: George has a total of B books in his library, 25 of which are hardcove
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04 Jul 2016, 00:11
anurag16 wrote: IMO A...
What is the OA and OE? The OA is E. Please refer to the solutions above and ask if anything remains unclear.
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Re: George has a total of B books in his library, 25 of which are hardcove
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04 Jul 2016, 00:18
Oh did a blunder!! Now Got it!! Thanks Bunuel



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Re: George has a total of B books in his library, 25 of which are hardcove
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04 Jul 2016, 12:41
A couple of ways to solve this question: Venn Diagram Method: https://youtu.be/5G5IwHoHjgkChart Method: https://www.youtube.com/watch?v=DCnr_4rNFI



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Re: George has a total of B books in his library, 25 of which are hardcove
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20 Aug 2016, 00:31
In this kind of DS questions are fiction/nonfiction and hardcover/paperback options exhaustive? If there is no note that he has only these kinds of books, we can't assume it, right?



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Re: George has a total of B books in his library, 25 of which are hardcove
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20 Aug 2016, 00:53
manlog wrote: In this kind of DS questions are fiction/nonfiction and hardcover/paperback options exhaustive? If there is no note that he has only these kinds of books, we can't assume it, right? We cannot assume that because each of the statements clearly stated " and the rest ", implying other options could not be assumed.
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George has a total of B books in his library, 25 of which are hardcove
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09 May 2017, 03:18
There are 4 categories of Books P = Fiction & Hardcover Q = Fiction & Paperback R = NonFiction & Hardcover S = NonFiction & Paperback
P+Q+R+S = B (given) P = 25 Find Value of B
STMT 01: P+Q = 40 P=25 => Q = 15 P+Q+R+S = B 40+R+S = B Since values of R & S are unknown. This stmt is insufficient.
STMT 02: P + R = 60 P=25 => R = 35 Q+S+60 = S Since values of Q & S are unknow. This stmt is insufficient
STMT 01 & 02: P=25 ; Q=15 ; R = 35 ; S = ? P+Q+R+S = B 75+S = B Still value of S is unknown. Hence E.



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Re: George has a total of B books in his library, 25 of which are hardcove
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29 Aug 2018, 00:56
Bunuel wrote: George has a total of B books in his library, 25 of which are hardcover fiction books. What is the value of B?
(1) 40 of the B books are fiction and the rest are nonfiction (2) 60 of the B books are hardcovers and the rest are paperbacks It also took very long for me. After giving a thought again, I realized that it can be solved very easily by a table format. fiction Non  Hardcover 25 35 from 2nd = 60  Paper 15 PF x  no info  Total 40 from 1st So E.



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Re: George has a total of B books in his library, 25 of which are hardcove
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30 Aug 2018, 14:24
I completely agree that this question can be answered efficiently using a matrix box approach, also known as the double matrix. The one thing I want to add to this discussion is to answer the question: How do we know that we can use a matrix box on this question? Whenever we see that a group can be divided into 2 parts in 2 different ways, we can use a matrix box. In this case, George's books can be divided into fiction and nonfiction (1st way) and hardcover and paperback (2nd way). This tells us that we can use a matrix box. I hope that this helps others to more quickly recognize that a matrix box or double matrix will be useful on questions like these. If you want more practice on recognizing and using matrix boxes, please visit the following link, where I have compiled a list of questions on which you can use matrix boxes: Matrix Boxes
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Re: George has a total of B books in his library, 25 of which are hardcove
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02 Sep 2018, 02:57
Answer is E
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George.xlsx [27.36 KiB]
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George has a total of B books in his library, 25 of which are hardcove
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11 Sep 2019, 05:16
How do I immediately see that the following matrix is not sufficient? I though I had enough equations to solve for B Bunuel?
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Screenshot 20190911 at 15.15.09.png [ 88.43 KiB  Viewed 4796 times ]
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Re: George has a total of B books in his library, 25 of which are hardcove
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12 Sep 2019, 04:06
ghnlrug wrote: How do I immediately see that the following matrix is not sufficient? I though I had enough equations to solve for B Bunuel? Plug some numbers there: if x = 0, then B = 75 but if x = 10, then B = 85.
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Re: George has a total of B books in his library, 25 of which are hardcove
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